Revert "Use FlutterFeatures to configure web and desktop devices (#36465)" (#36654)

This reverts commit bd52a78c7162e26721a383b76bac53744e5656a7.
diff --git a/dev/bots/test.dart b/dev/bots/test.dart
index 48be0bb..f103674 100644
--- a/dev/bots/test.dart
+++ b/dev/bots/test.dart
@@ -289,9 +289,6 @@
     workingDirectory: path.join(flutterRoot, relativePathToApplication),
     expectNonZeroExit: false,
     timeout: _kShortTimeout,
-    environment: <String, String>{
-      'FLUTTER_WEB': 'true',
-    }
   );
   print('Done.');
 }
diff --git a/packages/flutter_tools/lib/src/commands/assemble.dart b/packages/flutter_tools/lib/src/commands/assemble.dart
index 9919e65..e5a6659 100644
--- a/packages/flutter_tools/lib/src/commands/assemble.dart
+++ b/packages/flutter_tools/lib/src/commands/assemble.dart
@@ -30,6 +30,8 @@
   @override
   String get name => 'assemble';
 
+  @override
+  bool get isExperimental => true;
 
   @override
   Future<FlutterCommandResult> runCommand() {
@@ -125,6 +127,9 @@
   String get name => 'run';
 
   @override
+  bool get isExperimental => true;
+
+  @override
   Future<FlutterCommandResult> runCommand() async {
     final BuildResult result = await buildSystem.build(targetName, environment, BuildSystemConfig(
       resourcePoolSize: argResults['resource-pool-size'],
@@ -151,6 +156,9 @@
   String get name => 'describe';
 
   @override
+  bool get isExperimental => true;
+
+  @override
   Future<FlutterCommandResult> runCommand() {
     try {
       printStatus(
@@ -173,6 +181,9 @@
   String get name => 'inputs';
 
   @override
+  bool get isExperimental => true;
+
+  @override
   Future<FlutterCommandResult> runCommand() {
     try {
       final List<Map<String, Object>> results = buildSystem.describe(targetName, environment);
@@ -199,6 +210,9 @@
   String get name => 'build-dir';
 
   @override
+  bool get isExperimental => true;
+
+  @override
   Future<FlutterCommandResult> runCommand() {
     printStatus(environment.buildDir.path);
     return null;
diff --git a/packages/flutter_tools/lib/src/commands/build_bundle.dart b/packages/flutter_tools/lib/src/commands/build_bundle.dart
index d15cfa4..ef2235f 100644
--- a/packages/flutter_tools/lib/src/commands/build_bundle.dart
+++ b/packages/flutter_tools/lib/src/commands/build_bundle.dart
@@ -8,10 +8,10 @@
 import '../base/file_system.dart';
 import '../build_info.dart';
 import '../bundle.dart';
-import '../features.dart';
 import '../project.dart';
 import '../reporting/usage.dart';
 import '../runner/flutter_command.dart' show FlutterOptions, FlutterCommandResult;
+import '../version.dart';
 import 'build.dart';
 
 class BuildBundleCommand extends BuildSubCommand {
@@ -98,21 +98,13 @@
     if (platform == null) {
       throwToolExit('Unknown platform: $targetPlatform');
     }
-    // Check for target platforms that are only allowed via feature flags.
+    // Check for target platforms that are only allowed on unstable Flutter.
     switch (platform) {
       case TargetPlatform.darwin_x64:
-        if (!featureFlags.isMacOSEnabled) {
-          throwToolExit('macOS is not a supported target platform.');
-        }
-        break;
       case TargetPlatform.windows_x64:
-        if (!featureFlags.isWindowsEnabled) {
-          throwToolExit('Windows is not a supported target platform.');
-        }
-        break;
       case TargetPlatform.linux_x64:
-        if (!featureFlags.isLinuxEnabled) {
-          throwToolExit('Linux is not a supported target platform.');
+        if (!FlutterVersion.instance.isMaster) {
+          throwToolExit('$targetPlatform is not supported on stable Flutter.');
         }
         break;
       default:
diff --git a/packages/flutter_tools/lib/src/commands/build_fuchsia.dart b/packages/flutter_tools/lib/src/commands/build_fuchsia.dart
index 39e0a84..473f943 100644
--- a/packages/flutter_tools/lib/src/commands/build_fuchsia.dart
+++ b/packages/flutter_tools/lib/src/commands/build_fuchsia.dart
@@ -25,6 +25,9 @@
   final String name = 'fuchsia';
 
   @override
+  bool isExperimental = true;
+
+  @override
   bool hidden = true;
 
   @override
diff --git a/packages/flutter_tools/lib/src/commands/build_linux.dart b/packages/flutter_tools/lib/src/commands/build_linux.dart
index e75e411..4175b6d 100644
--- a/packages/flutter_tools/lib/src/commands/build_linux.dart
+++ b/packages/flutter_tools/lib/src/commands/build_linux.dart
@@ -8,7 +8,6 @@
 import '../base/platform.dart';
 import '../build_info.dart';
 import '../cache.dart';
-import '../features.dart';
 import '../linux/build_linux.dart';
 import '../project.dart';
 import '../runner/flutter_command.dart' show FlutterCommandResult;
@@ -36,6 +35,9 @@
   final String name = 'linux';
 
   @override
+  bool isExperimental = true;
+
+  @override
   bool hidden = true;
 
   @override
@@ -52,9 +54,6 @@
     Cache.releaseLockEarly();
     final BuildInfo buildInfo = getBuildInfo();
     final FlutterProject flutterProject = FlutterProject.current();
-    if (!featureFlags.isLinuxEnabled) {
-      throwToolExit('"build linux" is not currently supported.');
-    }
     if (!platform.isLinux) {
       throwToolExit('"build linux" only supported on Linux hosts.');
     }
diff --git a/packages/flutter_tools/lib/src/commands/build_macos.dart b/packages/flutter_tools/lib/src/commands/build_macos.dart
index f871186..e773f42 100644
--- a/packages/flutter_tools/lib/src/commands/build_macos.dart
+++ b/packages/flutter_tools/lib/src/commands/build_macos.dart
@@ -8,7 +8,6 @@
 import '../base/platform.dart';
 import '../build_info.dart';
 import '../cache.dart';
-import '../features.dart';
 import '../macos/build_macos.dart';
 import '../project.dart';
 import '../runner/flutter_command.dart' show FlutterCommandResult;
@@ -36,6 +35,9 @@
   final String name = 'macos';
 
   @override
+  bool isExperimental = true;
+
+  @override
   bool hidden = true;
 
   @override
@@ -45,16 +47,13 @@
   };
 
   @override
-  String get description => 'build the macOS desktop target.';
+  String get description => 'build the macOS desktop target (Experimental).';
 
   @override
   Future<FlutterCommandResult> runCommand() async {
     Cache.releaseLockEarly();
     final BuildInfo buildInfo = getBuildInfo();
     final FlutterProject flutterProject = FlutterProject.current();
-    if (!featureFlags.isMacOSEnabled) {
-      throwToolExit('"build macos" is not currently supported.');
-    }
     if (!platform.isMacOS) {
       throwToolExit('"build macos" only supported on macOS hosts.');
     }
diff --git a/packages/flutter_tools/lib/src/commands/build_web.dart b/packages/flutter_tools/lib/src/commands/build_web.dart
index 575d1b0..32cea06 100644
--- a/packages/flutter_tools/lib/src/commands/build_web.dart
+++ b/packages/flutter_tools/lib/src/commands/build_web.dart
@@ -4,9 +4,7 @@
 
 import 'dart:async';
 
-import '../base/common.dart';
 import '../build_info.dart';
-import '../features.dart';
 import '../project.dart';
 import '../runner/flutter_command.dart'
     show DevelopmentArtifact, FlutterCommandResult;
@@ -34,13 +32,13 @@
   bool get hidden => true;
 
   @override
-  final String description = 'build a web application bundle.';
+  bool get isExperimental => true;
+
+  @override
+  final String description = '(EXPERIMENTAL) build a web application bundle.';
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    if (!featureFlags.isWebEnabled) {
-      throwToolExit('"build web" is not currently supported.');
-    }
     final FlutterProject flutterProject = FlutterProject.current();
     final String target = argResults['target'];
     final BuildInfo buildInfo = getBuildInfo();
diff --git a/packages/flutter_tools/lib/src/commands/build_windows.dart b/packages/flutter_tools/lib/src/commands/build_windows.dart
index e41de03..884d26f 100644
--- a/packages/flutter_tools/lib/src/commands/build_windows.dart
+++ b/packages/flutter_tools/lib/src/commands/build_windows.dart
@@ -8,7 +8,6 @@
 import '../base/platform.dart';
 import '../build_info.dart';
 import '../cache.dart';
-import '../features.dart';
 import '../project.dart';
 import '../runner/flutter_command.dart' show FlutterCommandResult;
 import '../windows/build_windows.dart';
@@ -36,6 +35,9 @@
   final String name = 'windows';
 
   @override
+  bool isExperimental = true;
+
+  @override
   bool hidden = true;
 
   @override
@@ -45,16 +47,13 @@
   };
 
   @override
-  String get description => 'build the desktop Windows target.';
+  String get description => 'build the desktop Windows target (Experimental).';
 
   @override
   Future<FlutterCommandResult> runCommand() async {
     Cache.releaseLockEarly();
     final FlutterProject flutterProject = FlutterProject.current();
     final BuildInfo buildInfo = getBuildInfo();
-    if (!featureFlags.isWindowsEnabled) {
-      throwToolExit('"build windows" is not currently supported.');
-    }
     if (!platform.isWindows) {
       throwToolExit('"build windows" only supported on Windows hosts.');
     }
diff --git a/packages/flutter_tools/lib/src/commands/create.dart b/packages/flutter_tools/lib/src/commands/create.dart
index 875beae..17458ee 100644
--- a/packages/flutter_tools/lib/src/commands/create.dart
+++ b/packages/flutter_tools/lib/src/commands/create.dart
@@ -20,7 +20,6 @@
 import '../convert.dart';
 import '../dart/pub.dart';
 import '../doctor.dart';
-import '../features.dart';
 import '../globals.dart';
 import '../project.dart';
 import '../reporting/usage.dart';
@@ -614,7 +613,7 @@
       'iosLanguage': iosLanguage,
       'flutterRevision': FlutterVersion.instance.frameworkRevision,
       'flutterChannel': FlutterVersion.instance.channel,
-      'web': web && featureFlags.isWebEnabled,
+      'web': web && FlutterVersion.instance.isMaster
     };
   }
 
diff --git a/packages/flutter_tools/lib/src/commands/run.dart b/packages/flutter_tools/lib/src/commands/run.dart
index 0254e3e..91de004 100644
--- a/packages/flutter_tools/lib/src/commands/run.dart
+++ b/packages/flutter_tools/lib/src/commands/run.dart
@@ -13,7 +13,6 @@
 import '../build_info.dart';
 import '../cache.dart';
 import '../device.dart';
-import '../features.dart';
 import '../globals.dart';
 import '../macos/xcode.dart';
 import '../project.dart';
@@ -411,11 +410,11 @@
       );
       flutterDevices.add(flutterDevice);
     }
-    // Only support "web mode" with a single web device due to resident runner
-    // refactoring required otherwise.
-    final bool webMode = featureFlags.isWebEnabled &&
-                         devices.length == 1  &&
-                         await devices.single.targetPlatform == TargetPlatform.web_javascript;
+    // Only support "web mode" on non-stable branches with a single web device
+    // in a "hot mode".
+    final bool webMode = FlutterVersion.instance.isMaster
+      && devices.length == 1
+      && await devices.single.targetPlatform == TargetPlatform.web_javascript;
 
     ResidentRunner runner;
     final String applicationBinaryPath = argResults['use-application-binary'];
diff --git a/packages/flutter_tools/lib/src/commands/unpack.dart b/packages/flutter_tools/lib/src/commands/unpack.dart
index 481c326..799815e 100644
--- a/packages/flutter_tools/lib/src/commands/unpack.dart
+++ b/packages/flutter_tools/lib/src/commands/unpack.dart
@@ -70,6 +70,9 @@
   bool get hidden => true;
 
   @override
+  bool get isExperimental => true;
+
+  @override
   Future<Set<DevelopmentArtifact>> get requiredArtifacts async {
     final Set<DevelopmentArtifact> result = <DevelopmentArtifact>{
       DevelopmentArtifact.universal,
diff --git a/packages/flutter_tools/lib/src/desktop.dart b/packages/flutter_tools/lib/src/desktop.dart
index e62c4e7..501e241 100644
--- a/packages/flutter_tools/lib/src/desktop.dart
+++ b/packages/flutter_tools/lib/src/desktop.dart
@@ -4,10 +4,32 @@
 
 import 'dart:async';
 
+import 'package:meta/meta.dart';
+
+import 'base/common.dart';
 import 'base/io.dart';
+import 'base/platform.dart';
 import 'base/process_manager.dart';
 import 'convert.dart';
 import 'device.dart';
+import 'version.dart';
+
+@visibleForTesting
+bool debugDisableDesktop = false;
+
+/// Only launch or display desktop embedding devices from the command line
+/// or if `ENABLE_FLUTTER_DESKTOP` environment variable is set to true.
+bool get flutterDesktopEnabled {
+  if (debugDisableDesktop) {
+    return false;
+  }
+  if (isRunningFromDaemon) {
+    final bool platformEnabled = platform
+        .environment['ENABLE_FLUTTER_DESKTOP']?.toLowerCase() == 'true';
+    return platformEnabled && FlutterVersion.instance.isMaster;
+  }
+  return FlutterVersion.instance.isMaster;
+}
 
 /// Kills a process on linux or macOS.
 Future<bool> killProcess(String executable) async {
diff --git a/packages/flutter_tools/lib/src/device.dart b/packages/flutter_tools/lib/src/device.dart
index 734172f..936bf15 100644
--- a/packages/flutter_tools/lib/src/device.dart
+++ b/packages/flutter_tools/lib/src/device.dart
@@ -14,7 +14,9 @@
 import 'base/file_system.dart';
 import 'base/utils.dart';
 import 'build_info.dart';
+import 'desktop.dart';
 import 'fuchsia/fuchsia_device.dart';
+
 import 'globals.dart';
 import 'ios/devices.dart';
 import 'ios/simulators.dart';
@@ -23,6 +25,7 @@
 import 'project.dart';
 import 'tester/flutter_tester.dart';
 import 'web/web_device.dart';
+import 'web/workflow.dart';
 import 'windows/windows_device.dart';
 
 DeviceManager get deviceManager => context.get<DeviceManager>();
@@ -71,11 +74,23 @@
     IOSSimulators(),
     FuchsiaDevices(),
     FlutterTesterDevices(),
-    MacOSDevices(),
-    LinuxDevices(),
-    WindowsDevices(),
-    WebDevices(),
-  ]);
+  ] + _conditionalDesktopDevices + _conditionalWebDevices);
+
+  /// Only add desktop devices if the flag is enabled.
+  static List<DeviceDiscovery> get _conditionalDesktopDevices {
+    return flutterDesktopEnabled ? <DeviceDiscovery>[
+      MacOSDevices(),
+      LinuxDevices(),
+      WindowsDevices(),
+    ] : <DeviceDiscovery>[];
+  }
+
+  /// Only add web devices if the flag is enabled.
+  static List<DeviceDiscovery> get _conditionalWebDevices {
+    return flutterWebEnabled ? <DeviceDiscovery>[
+      WebDevices(),
+    ] : <DeviceDiscovery>[];
+  }
 
   String _specifiedDeviceId;
 
diff --git a/packages/flutter_tools/lib/src/doctor.dart b/packages/flutter_tools/lib/src/doctor.dart
index cf697c7..fa4081d 100644
--- a/packages/flutter_tools/lib/src/doctor.dart
+++ b/packages/flutter_tools/lib/src/doctor.dart
@@ -19,6 +19,7 @@
 import 'base/utils.dart';
 import 'base/version.dart';
 import 'cache.dart';
+import 'desktop.dart';
 import 'device.dart';
 import 'fuchsia/fuchsia_workflow.dart';
 import 'globals.dart';
@@ -73,10 +74,12 @@
           GroupedValidator(<DoctorValidator>[xcodeValidator, cocoapodsValidator]),
         if (webWorkflow.appliesToHostPlatform)
           const WebValidator(),
-        if (linuxWorkflow.appliesToHostPlatform)
-          LinuxDoctorValidator(),
-        if (windowsWorkflow.appliesToHostPlatform)
-          visualStudioValidator,
+        // Add desktop doctors to workflow if the flag is enabled.
+        if (flutterDesktopEnabled)
+          ...<DoctorValidator>[
+            if (linuxWorkflow.appliesToHostPlatform) LinuxDoctorValidator(),
+            if (windowsWorkflow.appliesToHostPlatform) visualStudioValidator,
+          ],
         if (ideValidators.isNotEmpty)
           ...ideValidators
         else
diff --git a/packages/flutter_tools/lib/src/linux/linux_workflow.dart b/packages/flutter_tools/lib/src/linux/linux_workflow.dart
index e51c26b..4959f72 100644
--- a/packages/flutter_tools/lib/src/linux/linux_workflow.dart
+++ b/packages/flutter_tools/lib/src/linux/linux_workflow.dart
@@ -4,8 +4,8 @@
 
 import '../base/context.dart';
 import '../base/platform.dart';
+import '../desktop.dart';
 import '../doctor.dart';
-import '../features.dart';
 
 /// The [WindowsWorkflow] instance.
 LinuxWorkflow get linuxWorkflow => context.get<LinuxWorkflow>();
@@ -18,13 +18,13 @@
   const LinuxWorkflow();
 
   @override
-  bool get appliesToHostPlatform => platform.isLinux && featureFlags.isLinuxEnabled;
+  bool get appliesToHostPlatform => platform.isLinux;
 
   @override
-  bool get canLaunchDevices => platform.isLinux && featureFlags.isLinuxEnabled;
+  bool get canLaunchDevices => platform.isLinux && flutterDesktopEnabled;
 
   @override
-  bool get canListDevices => platform.isLinux && featureFlags.isLinuxEnabled;
+  bool get canListDevices => platform.isLinux && flutterDesktopEnabled;
 
   @override
   bool get canListEmulators => false;
diff --git a/packages/flutter_tools/lib/src/macos/macos_workflow.dart b/packages/flutter_tools/lib/src/macos/macos_workflow.dart
index 1c0391f..e85e3d4 100644
--- a/packages/flutter_tools/lib/src/macos/macos_workflow.dart
+++ b/packages/flutter_tools/lib/src/macos/macos_workflow.dart
@@ -4,8 +4,8 @@
 
 import '../base/context.dart';
 import '../base/platform.dart';
+import '../desktop.dart';
 import '../doctor.dart';
-import '../features.dart';
 
 /// The [MacOSWorkflow] instance.
 MacOSWorkflow get macOSWorkflow => context.get<MacOSWorkflow>();
@@ -18,13 +18,13 @@
   const MacOSWorkflow();
 
   @override
-  bool get appliesToHostPlatform => platform.isMacOS && featureFlags.isMacOSEnabled;
+  bool get appliesToHostPlatform => platform.isMacOS;
 
   @override
-  bool get canLaunchDevices => platform.isMacOS && featureFlags.isMacOSEnabled;
+  bool get canLaunchDevices => platform.isMacOS && flutterDesktopEnabled;
 
   @override
-  bool get canListDevices => platform.isMacOS && featureFlags.isMacOSEnabled;
+  bool get canListDevices => platform.isMacOS && flutterDesktopEnabled;
 
   @override
   bool get canListEmulators => false;
diff --git a/packages/flutter_tools/lib/src/plugins.dart b/packages/flutter_tools/lib/src/plugins.dart
index 021ec84..0242a62 100644
--- a/packages/flutter_tools/lib/src/plugins.dart
+++ b/packages/flutter_tools/lib/src/plugins.dart
@@ -9,7 +9,7 @@
 
 import 'base/file_system.dart';
 import 'dart/package_map.dart';
-import 'features.dart';
+import 'desktop.dart';
 import 'globals.dart';
 import 'macos/cocoapods.dart';
 import 'project.dart';
@@ -364,7 +364,7 @@
   // TODO(stuartmorgan): Revisit the condition here once the plans for handling
   // desktop in existing projects are in place. For now, ignore checkProjects
   // on desktop and always treat it as true.
-  if (featureFlags.isMacOSEnabled && project.macos.existsSync()) {
+  if (flutterDesktopEnabled && project.macos.existsSync()) {
     await _writeMacOSPluginRegistrant(project, plugins);
   }
   for (final XcodeBasedProject subproject in <XcodeBasedProject>[project.ios, project.macos]) {
diff --git a/packages/flutter_tools/lib/src/project.dart b/packages/flutter_tools/lib/src/project.dart
index 95b526e..0a1b5b8 100644
--- a/packages/flutter_tools/lib/src/project.dart
+++ b/packages/flutter_tools/lib/src/project.dart
@@ -14,7 +14,7 @@
 import 'build_info.dart';
 import 'bundle.dart' as bundle;
 import 'cache.dart';
-import 'features.dart';
+import 'desktop.dart';
 import 'flutter_manifest.dart';
 import 'globals.dart';
 import 'ios/ios_workflow.dart';
@@ -22,6 +22,7 @@
 import 'ios/xcodeproj.dart' as xcode;
 import 'plugins.dart';
 import 'template.dart';
+import 'web/workflow.dart';
 
 FlutterProjectFactory get projectFactory => context.get<FlutterProjectFactory>() ?? const FlutterProjectFactory();
 
@@ -205,10 +206,10 @@
     }
     // TODO(stuartmorgan): Add checkProjects logic once a create workflow exists
     // for macOS. For now, always treat checkProjects as true for macOS.
-    if (featureFlags.isMacOSEnabled && macos.existsSync()) {
+    if (flutterDesktopEnabled && macos.existsSync()) {
       await macos.ensureReadyForPlatformSpecificTooling();
     }
-    if (featureFlags.isWebEnabled && web.existsSync()) {
+    if (flutterWebEnabled && web.existsSync()) {
       await web.ensureReadyForPlatformSpecificTooling();
     }
     await injectPlugins(this, checkProjects: checkProjects);
diff --git a/packages/flutter_tools/lib/src/runner/flutter_command.dart b/packages/flutter_tools/lib/src/runner/flutter_command.dart
index 2f56364..e9d9211 100644
--- a/packages/flutter_tools/lib/src/runner/flutter_command.dart
+++ b/packages/flutter_tools/lib/src/runner/flutter_command.dart
@@ -25,10 +25,10 @@
 import '../dart/pub.dart';
 import '../device.dart';
 import '../doctor.dart';
-import '../features.dart';
 import '../globals.dart';
 import '../project.dart';
 import '../reporting/usage.dart';
+import '../version.dart';
 import 'flutter_command_runner.dart';
 
 export '../cache.dart' show DevelopmentArtifact;
@@ -355,6 +355,11 @@
     }
   }
 
+  /// Whether this feature should not be usable on stable branches.
+  ///
+  /// Defaults to false, meaning it is usable.
+  bool get isExperimental => false;
+
   /// Additional usage values to be sent with the usage ping.
   Future<Map<String, String>> get usageValues async => const <String, String>{};
 
@@ -550,6 +555,12 @@
   @protected
   @mustCallSuper
   Future<void> validateCommand() async {
+    // If we're on a stable branch, then don't allow the usage of
+    // "experimental" features.
+    if (isExperimental && !FlutterVersion.instance.isMaster) {
+      throwToolExit('Experimental feature $name is not supported on stable branches');
+    }
+
     if (_requiresPubspecYaml && !PackageMap.isUsingCustomPackagesPath) {
       // Don't expect a pubspec.yaml file if the user passed in an explicit .packages file path.
       if (!fs.isFileSync('pubspec.yaml')) {
@@ -642,17 +653,17 @@
     case TargetPlatform.ios:
       return DevelopmentArtifact.iOS;
     case TargetPlatform.darwin_x64:
-      if (featureFlags.isMacOSEnabled) {
+      if (FlutterVersion.instance.isMaster) {
         return DevelopmentArtifact.macOS;
       }
       return null;
     case TargetPlatform.windows_x64:
-      if (featureFlags.isWindowsEnabled) {
+      if (!FlutterVersion.instance.isMaster) {
         return DevelopmentArtifact.windows;
       }
       return null;
     case TargetPlatform.linux_x64:
-      if (featureFlags.isLinuxEnabled) {
+      if (!FlutterVersion.instance.isMaster) {
         return DevelopmentArtifact.linux;
       }
       return null;
diff --git a/packages/flutter_tools/lib/src/web/web_device.dart b/packages/flutter_tools/lib/src/web/web_device.dart
index 689eb72..ecd8f41 100644
--- a/packages/flutter_tools/lib/src/web/web_device.dart
+++ b/packages/flutter_tools/lib/src/web/web_device.dart
@@ -11,7 +11,6 @@
 import '../base/process_manager.dart';
 import '../build_info.dart';
 import '../device.dart';
-import '../features.dart';
 import '../project.dart';
 import 'chrome.dart';
 import 'workflow.dart';
@@ -75,7 +74,7 @@
   Future<String> get emulatorId async => null;
 
   @override
-  bool isSupported() =>  featureFlags.isWebEnabled && canFindChrome();
+  bool isSupported() => flutterWebEnabled && canFindChrome();
 
   @override
   String get name => 'Chrome';
@@ -152,7 +151,7 @@
   final ChromeDevice _webDevice = ChromeDevice();
 
   @override
-  bool get canListAnything => featureFlags.isWebEnabled;
+  bool get canListAnything => flutterWebEnabled;
 
   @override
   Future<List<Device>> pollingGetDevices() async {
@@ -162,7 +161,7 @@
   }
 
   @override
-  bool get supportsPlatform =>  featureFlags.isWebEnabled;
+  bool get supportsPlatform => flutterWebEnabled;
 }
 
 @visibleForTesting
diff --git a/packages/flutter_tools/lib/src/web/workflow.dart b/packages/flutter_tools/lib/src/web/workflow.dart
index 1f388ca..925ec3d 100644
--- a/packages/flutter_tools/lib/src/web/workflow.dart
+++ b/packages/flutter_tools/lib/src/web/workflow.dart
@@ -2,13 +2,33 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:meta/meta.dart';
+
+import '../base/common.dart';
 import '../base/context.dart';
 import '../base/platform.dart';
 import '../base/process_manager.dart';
 import '../doctor.dart';
-import '../features.dart';
+import '../version.dart';
 import 'chrome.dart';
 
+@visibleForTesting
+bool debugDisableWeb = false;
+
+/// Only launch or display web devices if `FLUTTER_WEB`
+/// environment variable is set to true from the daemon.
+bool get flutterWebEnabled {
+  if (debugDisableWeb) {
+    return false;
+  }
+  if (isRunningFromDaemon) {
+    final bool platformEnabled = platform
+        .environment['FLUTTER_WEB']?.toLowerCase() == 'true';
+    return platformEnabled && FlutterVersion.instance.isMaster;
+  }
+  return FlutterVersion.instance.isMaster;
+}
+
 /// The  web workflow instance.
 WebWorkflow get webWorkflow => context.get<WebWorkflow>();
 
@@ -16,13 +36,13 @@
   const WebWorkflow();
 
   @override
-  bool get appliesToHostPlatform => featureFlags.isWebEnabled && (platform.isWindows || platform.isMacOS || platform.isLinux);
+  bool get appliesToHostPlatform => flutterWebEnabled && (platform.isWindows || platform.isMacOS || platform.isLinux);
 
   @override
-  bool get canLaunchDevices => featureFlags.isWebEnabled && canFindChrome();
+  bool get canLaunchDevices => flutterWebEnabled && canFindChrome();
 
   @override
-  bool get canListDevices => featureFlags.isWebEnabled && canFindChrome();
+  bool get canListDevices => flutterWebEnabled && canFindChrome();
 
   @override
   bool get canListEmulators => false;
diff --git a/packages/flutter_tools/lib/src/windows/windows_workflow.dart b/packages/flutter_tools/lib/src/windows/windows_workflow.dart
index 2a423bb..8d8e34e 100644
--- a/packages/flutter_tools/lib/src/windows/windows_workflow.dart
+++ b/packages/flutter_tools/lib/src/windows/windows_workflow.dart
@@ -4,8 +4,8 @@
 
 import '../base/context.dart';
 import '../base/platform.dart';
+import '../desktop.dart';
 import '../doctor.dart';
-import '../features.dart';
 
 /// The [WindowsWorkflow] instance.
 WindowsWorkflow get windowsWorkflow => context.get<WindowsWorkflow>();
@@ -18,13 +18,13 @@
   const WindowsWorkflow();
 
   @override
-  bool get appliesToHostPlatform => platform.isWindows && featureFlags.isWindowsEnabled;
+  bool get appliesToHostPlatform => platform.isWindows;
 
   @override
-  bool get canLaunchDevices => platform.isWindows && featureFlags.isWindowsEnabled;
+  bool get canLaunchDevices => platform.isWindows && flutterDesktopEnabled;
 
   @override
-  bool get canListDevices => platform.isWindows && featureFlags.isWindowsEnabled;
+  bool get canListDevices => platform.isWindows && flutterDesktopEnabled;
 
   @override
   bool get canListEmulators => false;
diff --git a/packages/flutter_tools/test/general.shard/commands/build_bundle_test.dart b/packages/flutter_tools/test/general.shard/commands/build_bundle_test.dart
index 782ac26..23e7a41 100644
--- a/packages/flutter_tools/test/general.shard/commands/build_bundle_test.dart
+++ b/packages/flutter_tools/test/general.shard/commands/build_bundle_test.dart
@@ -3,196 +3,93 @@
 // found in the LICENSE file.
 
 import 'package:args/command_runner.dart';
-import 'package:file/memory.dart';
-import 'package:flutter_tools/src/base/common.dart';
 import 'package:flutter_tools/src/base/file_system.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/commands/build_bundle.dart';
 import 'package:flutter_tools/src/bundle.dart';
-import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/reporting/usage.dart';
 import 'package:mockito/mockito.dart';
 
 import '../../src/common.dart';
 import '../../src/context.dart';
-import '../../src/testbed.dart';
 
 void main() {
   Cache.disableLocking();
-  Directory tempDir;
-  MockBundleBuilder mockBundleBuilder;
 
-  setUp(() {
-    tempDir = fs.systemTempDirectory.createTempSync('flutter_tools_packages_test.');
+  group('getUsage', () {
+    Directory tempDir;
+    MockBundleBuilder mockBundleBuilder;
 
-    mockBundleBuilder = MockBundleBuilder();
-    when(
-      mockBundleBuilder.build(
-        platform: anyNamed('platform'),
-        buildMode: anyNamed('buildMode'),
-        mainPath: anyNamed('mainPath'),
-        manifestPath: anyNamed('manifestPath'),
-        applicationKernelFilePath: anyNamed('applicationKernelFilePath'),
-        depfilePath: anyNamed('depfilePath'),
-        privateKeyPath: anyNamed('privateKeyPath'),
-        assetDirPath: anyNamed('assetDirPath'),
-        packagesPath: anyNamed('packagesPath'),
-        precompiledSnapshot: anyNamed('precompiledSnapshot'),
-        reportLicensedPackages: anyNamed('reportLicensedPackages'),
-        trackWidgetCreation: anyNamed('trackWidgetCreation'),
-        extraFrontEndOptions: anyNamed('extraFrontEndOptions'),
-        extraGenSnapshotOptions: anyNamed('extraGenSnapshotOptions'),
-        fileSystemRoots: anyNamed('fileSystemRoots'),
-        fileSystemScheme: anyNamed('fileSystemScheme'),
-      ),
-    ).thenAnswer((_) => Future<void>.value());
-  });
+    setUp(() {
+      tempDir = fs.systemTempDirectory.createTempSync('flutter_tools_packages_test.');
 
-  tearDown(() {
-    tryToDelete(tempDir);
-  });
+      mockBundleBuilder = MockBundleBuilder();
+      when(
+        mockBundleBuilder.build(
+          platform: anyNamed('platform'),
+          buildMode: anyNamed('buildMode'),
+          mainPath: anyNamed('mainPath'),
+          manifestPath: anyNamed('manifestPath'),
+          applicationKernelFilePath: anyNamed('applicationKernelFilePath'),
+          depfilePath: anyNamed('depfilePath'),
+          privateKeyPath: anyNamed('privateKeyPath'),
+          assetDirPath: anyNamed('assetDirPath'),
+          packagesPath: anyNamed('packagesPath'),
+          precompiledSnapshot: anyNamed('precompiledSnapshot'),
+          reportLicensedPackages: anyNamed('reportLicensedPackages'),
+          trackWidgetCreation: anyNamed('trackWidgetCreation'),
+          extraFrontEndOptions: anyNamed('extraFrontEndOptions'),
+          extraGenSnapshotOptions: anyNamed('extraGenSnapshotOptions'),
+          fileSystemRoots: anyNamed('fileSystemRoots'),
+          fileSystemScheme: anyNamed('fileSystemScheme'),
+        ),
+      ).thenAnswer((_) => Future<void>.value());
+    });
 
-  Future<BuildBundleCommand> runCommandIn(String projectPath, { List<String> arguments }) async {
-    final BuildBundleCommand command = BuildBundleCommand(bundleBuilder: mockBundleBuilder);
-    final CommandRunner<void> runner = createTestCommandRunner(command);
-    await runner.run(<String>[
-      'bundle',
-      ...?arguments,
-      '--target=$projectPath/lib/main.dart',
-    ]);
-    return command;
-  }
+    tearDown(() {
+      tryToDelete(tempDir);
+    });
 
-  testUsingContext('bundle getUsage indicate that project is a module', () async {
-    final String projectPath = await createProject(tempDir,
-        arguments: <String>['--no-pub', '--template=module']);
+    Future<BuildBundleCommand> runCommandIn(String projectPath, { List<String> arguments }) async {
+      final BuildBundleCommand command = BuildBundleCommand(bundleBuilder: mockBundleBuilder);
+      final CommandRunner<void> runner = createTestCommandRunner(command);
+      await runner.run(<String>[
+        'bundle',
+        ...?arguments,
+        '--target=$projectPath/lib/main.dart',
+      ]);
+      return command;
+    }
 
-    final BuildBundleCommand command = await runCommandIn(projectPath);
+    testUsingContext('indicate that project is a module', () async {
+      final String projectPath = await createProject(tempDir,
+          arguments: <String>['--no-pub', '--template=module']);
 
-    expect(await command.usageValues,
-        containsPair(kCommandBuildBundleIsModule, 'true'));
-  }, timeout: allowForCreateFlutterProject);
+      final BuildBundleCommand command = await runCommandIn(projectPath);
 
-  testUsingContext('bundle getUsage indicate that project is not a module', () async {
-    final String projectPath = await createProject(tempDir,
-        arguments: <String>['--no-pub', '--template=app']);
+      expect(await command.usageValues,
+          containsPair(kCommandBuildBundleIsModule, 'true'));
+    }, timeout: allowForCreateFlutterProject);
 
-    final BuildBundleCommand command = await runCommandIn(projectPath);
+    testUsingContext('indicate that project is not a module', () async {
+      final String projectPath = await createProject(tempDir,
+          arguments: <String>['--no-pub', '--template=app']);
 
-    expect(await command.usageValues,
-        containsPair(kCommandBuildBundleIsModule, 'false'));
-  }, timeout: allowForCreateFlutterProject);
+      final BuildBundleCommand command = await runCommandIn(projectPath);
 
-  testUsingContext('bundle getUsage indicate the target platform', () async {
-    final String projectPath = await createProject(tempDir,
-        arguments: <String>['--no-pub', '--template=app']);
+      expect(await command.usageValues,
+          containsPair(kCommandBuildBundleIsModule, 'false'));
+    }, timeout: allowForCreateFlutterProject);
 
-    final BuildBundleCommand command = await runCommandIn(projectPath);
+    testUsingContext('indicate the target platform', () async {
+      final String projectPath = await createProject(tempDir,
+          arguments: <String>['--no-pub', '--template=app']);
 
-    expect(await command.usageValues,
-        containsPair(kCommandBuildBundleTargetPlatform, 'android-arm'));
-  }, timeout: allowForCreateFlutterProject);
+      final BuildBundleCommand command = await runCommandIn(projectPath);
 
-  testUsingContext('bundle fails to build for Windows if feature is disabled', () async {
-    fs.file('lib/main.dart').createSync(recursive: true);
-    fs.file('pubspec.yaml').createSync(recursive: true);
-    fs.file('.packages').createSync(recursive: true);
-    final CommandRunner<void> runner = createTestCommandRunner(BuildBundleCommand()
-        ..bundleBuilder = MockBundleBuilder());
-
-    expect(() => runner.run(<String>[
-      'bundle',
-      '--no-pub',
-      '--target-platform=windows-x64'
-    ]), throwsA(isInstanceOf<ToolExit>()));
-  }, overrides: <Type, Generator>{
-    FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: false),
-  });
-
-  testUsingContext('bundle fails to build for Linux if feature is disabled', () async {
-    fs.file('lib/main.dart').createSync(recursive: true);
-    fs.file('pubspec.yaml').createSync();
-    fs.file('.packages').createSync();
-    final CommandRunner<void> runner = createTestCommandRunner(BuildBundleCommand()
-        ..bundleBuilder = MockBundleBuilder());
-
-    expect(() => runner.run(<String>[
-      'bundle',
-      '--no-pub',
-      '--target-platform=linux-x64'
-    ]), throwsA(isInstanceOf<ToolExit>()));
-  }, overrides: <Type, Generator>{
-    FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: false),
-  });
-
-  testUsingContext('bundle fails to build for macOS if feature is disabled', () async {
-    fs.file('lib/main.dart').createSync(recursive: true);
-    fs.file('pubspec.yaml').createSync();
-    fs.file('.packages').createSync();
-    final CommandRunner<void> runner = createTestCommandRunner(BuildBundleCommand()
-        ..bundleBuilder = MockBundleBuilder());
-
-    expect(() => runner.run(<String>[
-      'bundle',
-      '--no-pub',
-      '--target-platform=darwin-x64'
-    ]), throwsA(isInstanceOf<ToolExit>()));
-  }, overrides: <Type, Generator>{
-    FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: false),
-  });
-
-  testUsingContext('bundle can build for Windows if feature is enabled', () async {
-    fs.file('lib/main.dart').createSync(recursive: true);
-    fs.file('pubspec.yaml').createSync();
-    fs.file('.packages').createSync();
-    final CommandRunner<void> runner = createTestCommandRunner(BuildBundleCommand()
-        ..bundleBuilder = MockBundleBuilder());
-
-    await runner.run(<String>[
-      'bundle',
-      '--no-pub',
-      '--target-platform=windows-x64'
-    ]);
-  }, overrides: <Type, Generator>{
-    FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: true),
-  });
-
-  testUsingContext('bundle can build for Linux if feature is enabled', () async {
-    fs.file('lib/main.dart').createSync(recursive: true);
-    fs.file('pubspec.yaml').createSync();
-    fs.file('.packages').createSync();
-    final CommandRunner<void> runner = createTestCommandRunner(BuildBundleCommand()
-        ..bundleBuilder = MockBundleBuilder());
-
-    await runner.run(<String>[
-      'bundle',
-      '--no-pub',
-      '--target-platform=linux-x64'
-    ]);
-  }, overrides: <Type, Generator>{
-    FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: true),
-  });
-
-  testUsingContext('bundle can build for macOS if feature is enabled', () async {
-    fs.file('lib/main.dart').createSync(recursive: true);
-    fs.file('pubspec.yaml').createSync();
-    fs.file('.packages').createSync();
-    final CommandRunner<void> runner = createTestCommandRunner(BuildBundleCommand()
-        ..bundleBuilder = MockBundleBuilder());
-
-    await runner.run(<String>[
-      'bundle',
-      '--no-pub',
-      '--target-platform=darwin-x64'
-    ]);
-  }, overrides: <Type, Generator>{
-    FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: true),
+      expect(await command.usageValues,
+          containsPair(kCommandBuildBundleTargetPlatform, 'android-arm'));
+    }, timeout: allowForCreateFlutterProject);
   });
 }
 
diff --git a/packages/flutter_tools/test/general.shard/commands/build_linux_test.dart b/packages/flutter_tools/test/general.shard/commands/build_linux_test.dart
index 0e1c809..638a20b 100644
--- a/packages/flutter_tools/test/general.shard/commands/build_linux_test.dart
+++ b/packages/flutter_tools/test/general.shard/commands/build_linux_test.dart
@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:args/command_runner.dart';
 import 'package:file/memory.dart';
 import 'package:flutter_tools/src/base/common.dart';
 import 'package:flutter_tools/src/base/file_system.dart';
@@ -10,7 +9,6 @@
 import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/commands/build.dart';
-import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/linux/makefile.dart';
 import 'package:flutter_tools/src/project.dart';
 import 'package:mockito/mockito.dart';
@@ -19,7 +17,6 @@
 import '../../src/common.dart';
 import '../../src/context.dart';
 import '../../src/mocks.dart';
-import '../../src/testbed.dart';
 
 void main() {
   MockProcessManager mockProcessManager;
@@ -58,7 +55,6 @@
   }, overrides: <Type, Generator>{
     Platform: () => linuxPlatform,
     FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: true),
   });
 
   testUsingContext('Linux build fails on non-linux platform', () async {
@@ -75,7 +71,6 @@
   }, overrides: <Type, Generator>{
     Platform: () => notLinuxPlatform,
     FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: true),
   });
 
   testUsingContext('Linux build invokes make and writes temporary files', () async {
@@ -102,7 +97,6 @@
     FileSystem: () => MemoryFileSystem(),
     ProcessManager: () => mockProcessManager,
     Platform: () => linuxPlatform,
-    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: true),
   });
 
   testUsingContext('linux can extract binary name from Makefile', () async {
@@ -118,19 +112,7 @@
     final FlutterProject flutterProject = FlutterProject.current();
 
     expect(makefileExecutableName(flutterProject.linux), 'fizz_bar');
-  }, overrides: <Type, Generator>{
-    FileSystem: () => MemoryFileSystem(),
-    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: true),
-  });
-
-  testUsingContext('Refuses to build for Linux when feature is disabled', () {
-    final CommandRunner<void> runner = createTestCommandRunner(BuildCommand());
-
-    expect(() => runner.run(<String>['build', 'linux']),
-        throwsA(isInstanceOf<ToolExit>()));
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: false),
-  });
+  }, overrides: <Type, Generator>{FileSystem: () => MemoryFileSystem()});
 }
 
 class MockProcessManager extends Mock implements ProcessManager {}
diff --git a/packages/flutter_tools/test/general.shard/commands/build_macos_test.dart b/packages/flutter_tools/test/general.shard/commands/build_macos_test.dart
index 462e2d8..ceb07b8 100644
--- a/packages/flutter_tools/test/general.shard/commands/build_macos_test.dart
+++ b/packages/flutter_tools/test/general.shard/commands/build_macos_test.dart
@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:args/command_runner.dart';
 import 'package:file/memory.dart';
 import 'package:flutter_tools/src/base/common.dart';
 import 'package:flutter_tools/src/base/file_system.dart';
@@ -11,7 +10,6 @@
 import 'package:flutter_tools/src/build_info.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/commands/build.dart';
-import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/project.dart';
 import 'package:mockito/mockito.dart';
 import 'package:process/process.dart';
@@ -19,7 +17,6 @@
 import '../../src/common.dart';
 import '../../src/context.dart';
 import '../../src/mocks.dart';
-import '../../src/testbed.dart';
 
 void main() {
   MockProcessManager mockProcessManager;
@@ -59,7 +56,6 @@
     ), throwsA(isInstanceOf<ToolExit>()));
   }, overrides: <Type, Generator>{
     Platform: () => macosPlatform,
-    FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: true),
   });
 
   testUsingContext('macOS build fails on non-macOS platform', () async {
@@ -75,7 +71,6 @@
   }, overrides: <Type, Generator>{
     Platform: () => notMacosPlatform,
     FileSystem: () => memoryFilesystem,
-    FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: true),
   });
 
   testUsingContext('macOS build invokes build script', () async {
@@ -109,16 +104,6 @@
     FileSystem: () => memoryFilesystem,
     ProcessManager: () => mockProcessManager,
     Platform: () => macosPlatform,
-    FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: true),
-  });
-
-  testUsingContext('Refuses to build for macOS when feature is disabled', () {
-    final CommandRunner<void> runner = createTestCommandRunner(BuildCommand());
-
-    expect(() => runner.run(<String>['build', 'macos']),
-        throwsA(isInstanceOf<ToolExit>()));
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: false),
   });
 }
 
diff --git a/packages/flutter_tools/test/general.shard/commands/build_web_test.dart b/packages/flutter_tools/test/general.shard/commands/build_web_test.dart
index 3046570..2adb818 100644
--- a/packages/flutter_tools/test/general.shard/commands/build_web_test.dart
+++ b/packages/flutter_tools/test/general.shard/commands/build_web_test.dart
@@ -2,15 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:args/command_runner.dart';
 import 'package:flutter_tools/src/base/common.dart';
 import 'package:flutter_tools/src/base/file_system.dart';
 import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/build_info.dart';
 import 'package:flutter_tools/src/cache.dart';
-import 'package:flutter_tools/src/commands/build.dart';
 import 'package:flutter_tools/src/device.dart';
-import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/project.dart';
 import 'package:flutter_tools/src/resident_runner.dart';
 import 'package:flutter_tools/src/resident_web_runner.dart';
@@ -27,7 +24,6 @@
   MockPlatform mockPlatform;
 
   setUpAll(() {
-    Cache.flutterRoot = '';
     Cache.disableLocking();
   });
 
@@ -53,7 +49,6 @@
       WebCompilationProxy: () => mockWebCompilationProxy,
       Platform: () => mockPlatform,
       FlutterVersion: () => MockFlutterVersion(),
-      FeatureFlags: () => TestFeatureFlags(isWebEnabled: true),
     });
   });
 
@@ -87,15 +82,6 @@
       BuildInfo.debug,
     );
   }));
-
-  test('Refuses to build for web when feature is disabled', () => testbed.run(() async {
-    final CommandRunner<void> runner = createTestCommandRunner(BuildCommand());
-
-    expect(() => runner.run(<String>['build', 'web']),
-        throwsA(isInstanceOf<ToolExit>()));
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(isWebEnabled: false),
-  }));
 }
 
 class MockWebCompilationProxy extends Mock implements WebCompilationProxy {}
diff --git a/packages/flutter_tools/test/general.shard/commands/build_windows_test.dart b/packages/flutter_tools/test/general.shard/commands/build_windows_test.dart
index 948eae0..301fa7d 100644
--- a/packages/flutter_tools/test/general.shard/commands/build_windows_test.dart
+++ b/packages/flutter_tools/test/general.shard/commands/build_windows_test.dart
@@ -9,7 +9,6 @@
 import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/commands/build.dart';
-import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/windows/visual_studio.dart';
 import 'package:mockito/mockito.dart';
 import 'package:process/process.dart';
@@ -18,7 +17,6 @@
 import '../../src/common.dart';
 import '../../src/context.dart';
 import '../../src/mocks.dart';
-import '../../src/testbed.dart';
 
 void main() {
   MockProcessManager mockProcessManager;
@@ -67,7 +65,6 @@
     Platform: () => windowsPlatform,
     FileSystem: () => memoryFilesystem,
     VisualStudio: () => mockVisualStudio,
-    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: true),
   });
 
   testUsingContext('Windows build fails when there is no windows project', () async {
@@ -81,7 +78,6 @@
     Platform: () => windowsPlatform,
     FileSystem: () => memoryFilesystem,
     VisualStudio: () => mockVisualStudio,
-    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: true),
   });
 
   testUsingContext('Windows build fails on non windows platform', () async {
@@ -100,7 +96,6 @@
     Platform: () => notWindowsPlatform,
     FileSystem: () => memoryFilesystem,
     VisualStudio: () => mockVisualStudio,
-    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: true),
   });
 
   testUsingContext('Windows build invokes msbuild and writes generated files', () async {
@@ -137,7 +132,6 @@
     ProcessManager: () => mockProcessManager,
     Platform: () => windowsPlatform,
     VisualStudio: () => mockVisualStudio,
-    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: true),
   });
 }
 
diff --git a/packages/flutter_tools/test/general.shard/commands/devices_test.dart b/packages/flutter_tools/test/general.shard/commands/devices_test.dart
index ee6e095..01bbb9a 100644
--- a/packages/flutter_tools/test/general.shard/commands/devices_test.dart
+++ b/packages/flutter_tools/test/general.shard/commands/devices_test.dart
@@ -20,6 +20,9 @@
   group('devices', () {
     setUpAll(() {
       Cache.disableLocking();
+      // TODO(jonahwilliams): adjust the individual tests so they do not
+      // depend on the host environment.
+      debugDisableWebAndDesktop = true;
     });
 
     testUsingContext('returns 0 when called', () async {
diff --git a/packages/flutter_tools/test/general.shard/commands/update_packages_test.dart b/packages/flutter_tools/test/general.shard/commands/update_packages_test.dart
new file mode 100644
index 0000000..6097ba0
--- /dev/null
+++ b/packages/flutter_tools/test/general.shard/commands/update_packages_test.dart
@@ -0,0 +1,18 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_tools/src/commands/update_packages.dart';
+
+import '../../src/common.dart';
+import '../../src/context.dart';
+
+void main() {
+  group('UpdatePackagesCommand', () {
+    // Marking it as experimental breaks bots tests and packaging scripts on stable branches.
+    testUsingContext('is not marked as experimental', () async {
+      final UpdatePackagesCommand command = UpdatePackagesCommand();
+      expect(command.isExperimental, isFalse);
+    });
+  });
+}
diff --git a/packages/flutter_tools/test/general.shard/doctor.dart b/packages/flutter_tools/test/general.shard/doctor.dart
deleted file mode 100644
index db574e6..0000000
--- a/packages/flutter_tools/test/general.shard/doctor.dart
+++ /dev/null
@@ -1,62 +0,0 @@
-// Copyright 2019 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'package:flutter_tools/src/doctor.dart';
-import 'package:flutter_tools/src/features.dart';
-import 'package:flutter_tools/src/linux/linux_doctor.dart';
-import 'package:flutter_tools/src/web/web_validator.dart';
-import 'package:flutter_tools/src/windows/visual_studio_validator.dart';
-
-import '../src/common.dart';
-import '../src/testbed.dart';
-
-void main() {
-  Testbed testbed;
-
-  setUp(() {
-    testbed = Testbed();
-  });
-
-  test('doctor validators includes desktop when features are enabled', () => testbed.run(() {
-    expect(DoctorValidatorsProvider.defaultInstance.validators,
-        contains(isInstanceOf<LinuxDoctorValidator>()));
-    expect(DoctorValidatorsProvider.defaultInstance.validators,
-        contains(isInstanceOf<VisualStudioValidator>()));
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(
-      isLinuxEnabled: true,
-      isWindowsEnabled: true,
-    )
-  }));
-
-  test('doctor validators does not include desktop when features are enabled', () => testbed.run(() {
-    expect(DoctorValidatorsProvider.defaultInstance.validators,
-        isNot(contains(isInstanceOf<LinuxDoctorValidator>())));
-    expect(DoctorValidatorsProvider.defaultInstance.validators,
-        isNot(contains(isInstanceOf<VisualStudioValidator>())));
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(
-      isLinuxEnabled: false,
-      isWindowsEnabled: false,
-    )
-  }));
-
-  test('doctor validators includes web when feature is enabled', () => testbed.run(() {
-    expect(DoctorValidatorsProvider.defaultInstance.validators,
-        contains(isInstanceOf<WebValidator>()));
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(
-      isWebEnabled: true,
-    )
-  }));
-
-  test('doctor validators does not include web when feature is disabled', () => testbed.run(() {
-    expect(DoctorValidatorsProvider.defaultInstance.validators,
-        isNot(contains(isInstanceOf<WebValidator>())));
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(
-      isWebEnabled: false,
-    )
-  }));
-}
diff --git a/packages/flutter_tools/test/general.shard/linux/linux_workflow_test.dart b/packages/flutter_tools/test/general.shard/linux/linux_workflow_test.dart
index 8723c47..1445cff 100644
--- a/packages/flutter_tools/test/general.shard/linux/linux_workflow_test.dart
+++ b/packages/flutter_tools/test/general.shard/linux/linux_workflow_test.dart
@@ -2,57 +2,42 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:flutter_tools/src/features.dart';
 import 'package:mockito/mockito.dart';
 import 'package:flutter_tools/src/linux/linux_workflow.dart';
 import 'package:flutter_tools/src/base/platform.dart';
 
 import '../../src/common.dart';
 import '../../src/context.dart';
-import '../../src/testbed.dart';
 
 void main() {
-  MockPlatform linux;
-  MockPlatform notLinux;
-  Testbed testbed;
-
-  setUp(() {
-    linux = MockPlatform();
-    notLinux = MockPlatform();
+  group(LinuxWorkflow, () {
+    final MockPlatform linux = MockPlatform();
+    final MockPlatform linuxWithFde = MockPlatform()
+      ..environment['ENABLE_FLUTTER_DESKTOP'] = 'true';
+    final MockPlatform notLinux = MockPlatform();
     when(linux.isLinux).thenReturn(true);
+    when(linuxWithFde.isLinux).thenReturn(true);
     when(notLinux.isLinux).thenReturn(false);
-    testbed = Testbed(
-      overrides: <Type, Generator>{
-        Platform: () => linux,
-        FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: true),
-      }
-    );
+
+    testUsingContext('Applies to linux platform', () {
+      expect(linuxWorkflow.appliesToHostPlatform, true);
+    }, overrides: <Type, Generator>{
+      Platform: () => linux,
+    });
+    testUsingContext('Does not apply to non-linux platform', () {
+      expect(linuxWorkflow.appliesToHostPlatform, false);
+    }, overrides: <Type, Generator>{
+      Platform: () => notLinux,
+    });
+
+    testUsingContext('defaults', () {
+      expect(linuxWorkflow.canListEmulators, false);
+      expect(linuxWorkflow.canLaunchDevices, true);
+      expect(linuxWorkflow.canListDevices, true);
+    }, overrides: <Type, Generator>{
+      Platform: () => linuxWithFde,
+    });
   });
-
-  test('Applies to linux platform', () => testbed.run(() {
-    expect(linuxWorkflow.appliesToHostPlatform, true);
-    expect(linuxWorkflow.canLaunchDevices, true);
-    expect(linuxWorkflow.canListDevices, true);
-    expect(linuxWorkflow.canListEmulators, false);
-  }));
-
-  test('Does not apply to non-linux platform', () => testbed.run(() {
-    expect(linuxWorkflow.appliesToHostPlatform, false);
-    expect(linuxWorkflow.canLaunchDevices, false);
-    expect(linuxWorkflow.canListDevices, false);
-    expect(linuxWorkflow.canListEmulators, false);
-  }, overrides: <Type, Generator>{
-    Platform: () => notLinux,
-  }));
-
-  test('Does not apply when feature is disabled', () => testbed.run(() {
-    expect(linuxWorkflow.appliesToHostPlatform, false);
-    expect(linuxWorkflow.canLaunchDevices, false);
-    expect(linuxWorkflow.canListDevices, false);
-    expect(linuxWorkflow.canListEmulators, false);
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: false),
-  }));
 }
 
 class MockPlatform extends Mock implements Platform {
diff --git a/packages/flutter_tools/test/general.shard/macos/macos_workflow_test.dart b/packages/flutter_tools/test/general.shard/macos/macos_workflow_test.dart
index 9dadfe9..b63bdde 100644
--- a/packages/flutter_tools/test/general.shard/macos/macos_workflow_test.dart
+++ b/packages/flutter_tools/test/general.shard/macos/macos_workflow_test.dart
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:flutter_tools/src/features.dart';
+import 'package:flutter_tools/src/base/io.dart';
 import 'package:mockito/mockito.dart';
 
 import 'package:flutter_tools/src/base/platform.dart';
@@ -11,48 +11,40 @@
 
 import '../../src/common.dart';
 import '../../src/context.dart';
-import '../../src/testbed.dart';
 
 void main() {
-  MockPlatform mac;
-  MockPlatform notMac;
-  Testbed testbed;
-
-  setUp(() {
-    mac = MockPlatform();
-    notMac = MockPlatform();
+  group(MacOSWorkflow, () {
+    final MockPlatform mac = MockPlatform();
+    final MockPlatform macWithFde = MockPlatform()
+      ..environment['ENABLE_FLUTTER_DESKTOP'] = 'true';
+    final MockPlatform notMac = MockPlatform();
     when(mac.isMacOS).thenReturn(true);
+    when(macWithFde.isMacOS).thenReturn(true);
     when(notMac.isMacOS).thenReturn(false);
-    testbed = Testbed(overrides: <Type, Generator>{
+
+    final MockProcessManager mockProcessManager = MockProcessManager();
+    when(mockProcessManager.run(any)).thenAnswer((Invocation invocation) async {
+      return ProcessResult(0, 1, '', '');
+    });
+    testUsingContext('Applies to mac platform', () {
+      expect(macOSWorkflow.appliesToHostPlatform, true);
+    }, overrides: <Type, Generator>{
       Platform: () => mac,
-      FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: true),
+    });
+    testUsingContext('Does not apply to non-mac platform', () {
+      expect(macOSWorkflow.appliesToHostPlatform, false);
+    }, overrides: <Type, Generator>{
+      Platform: () => notMac,
+    });
+
+    testUsingContext('defaults', () {
+      expect(macOSWorkflow.canListEmulators, false);
+      expect(macOSWorkflow.canLaunchDevices, true);
+      expect(macOSWorkflow.canListDevices, true);
+    }, overrides: <Type, Generator>{
+      Platform: () => macWithFde,
     });
   });
-
-  test('Applies to macOS platform', () => testbed.run(() {
-    expect(macOSWorkflow.appliesToHostPlatform, true);
-    expect(macOSWorkflow.canListDevices, true);
-    expect(macOSWorkflow.canLaunchDevices, true);
-    expect(macOSWorkflow.canListEmulators, false);
-  }));
-
-  test('Does not apply to non-macOS platform', () => testbed.run(() {
-    expect(macOSWorkflow.appliesToHostPlatform, false);
-    expect(macOSWorkflow.canListDevices, false);
-    expect(macOSWorkflow.canLaunchDevices, false);
-    expect(macOSWorkflow.canListEmulators, false);
-  }, overrides: <Type, Generator>{
-    Platform: () => notMac,
-  }));
-
-  test('Does not apply when feature is disabled', () => testbed.run(() {
-    expect(macOSWorkflow.appliesToHostPlatform, false);
-    expect(macOSWorkflow.canListDevices, false);
-    expect(macOSWorkflow.canLaunchDevices, false);
-    expect(macOSWorkflow.canListEmulators, false);
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: false),
-  }));
 }
 
 class MockPlatform extends Mock implements Platform {
diff --git a/packages/flutter_tools/test/general.shard/runner/flutter_command_test.dart b/packages/flutter_tools/test/general.shard/runner/flutter_command_test.dart
index eb06c9d..c781e3c 100644
--- a/packages/flutter_tools/test/general.shard/runner/flutter_command_test.dart
+++ b/packages/flutter_tools/test/general.shard/runner/flutter_command_test.dart
@@ -243,6 +243,27 @@
       SystemClock: () => clock,
       Usage: () => usage,
     });
+
+  });
+
+  group('Experimental commands', () {
+    final MockVersion stableVersion = MockVersion();
+    final MockVersion betaVersion = MockVersion();
+    final FakeCommand fakeCommand = FakeCommand();
+    when(stableVersion.isMaster).thenReturn(false);
+    when(betaVersion.isMaster).thenReturn(true);
+
+    testUsingContext('Can be disabled on stable branch', () async {
+      expect(() => fakeCommand.run(), throwsA(isA<ToolExit>()));
+    }, overrides: <Type, Generator>{
+      FlutterVersion: () => stableVersion,
+    });
+
+    testUsingContext('Works normally on regular branches', () async {
+      expect(fakeCommand.run(), completes);
+    }, overrides: <Type, Generator>{
+      FlutterVersion: () => betaVersion,
+    });
   });
 }
 
@@ -255,6 +276,9 @@
   String get name => 'fake';
 
   @override
+  bool get isExperimental => true;
+
+  @override
   Future<FlutterCommandResult> runCommand() async {
     return null;
   }
diff --git a/packages/flutter_tools/test/general.shard/web/workflow_test.dart b/packages/flutter_tools/test/general.shard/web/workflow_test.dart
index ab11aea..86a8d6b 100644
--- a/packages/flutter_tools/test/general.shard/web/workflow_test.dart
+++ b/packages/flutter_tools/test/general.shard/web/workflow_test.dart
@@ -4,7 +4,7 @@
 
 import 'package:flutter_tools/src/base/file_system.dart';
 import 'package:flutter_tools/src/base/platform.dart';
-import 'package:flutter_tools/src/features.dart';
+import 'package:flutter_tools/src/version.dart';
 import 'package:flutter_tools/src/web/chrome.dart';
 import 'package:flutter_tools/src/web/workflow.dart';
 import 'package:mockito/mockito.dart';
@@ -22,9 +22,13 @@
     MockPlatform linux;
     MockPlatform macos;
     MockProcessManager mockProcessManager;
+    MockFlutterVersion unstable;
+    MockFlutterVersion stable;
     WebWorkflow workflow;
 
     setUpAll(() {
+      unstable = MockFlutterVersion(false);
+      stable = MockFlutterVersion(true);
       notSupported = MockPlatform(linux: false, windows: false, macos: false);
       windows = MockPlatform(windows: true);
       linux = MockPlatform(linux: true);
@@ -35,7 +39,7 @@
         fs.file('chrome').createSync();
         when(mockProcessManager.canRun('chrome')).thenReturn(true);
       }, overrides: <Type, Generator>{
-        FeatureFlags: () => TestFeatureFlags(isWebEnabled: true),
+        FlutterVersion: () => unstable,
         ProcessManager: () => mockProcessManager,
       });
     });
@@ -77,18 +81,27 @@
       Platform: () => notSupported,
     }));
 
-    test('does not apply if feature flag is disabled', () => testbed.run(() {
+    test('does not apply on stable branch', () => testbed.run(() {
       expect(workflow.appliesToHostPlatform, false);
       expect(workflow.canLaunchDevices, false);
       expect(workflow.canListDevices, false);
       expect(workflow.canListEmulators, false);
     }, overrides: <Type, Generator>{
       Platform: () => macos,
-      FeatureFlags: () => TestFeatureFlags(isWebEnabled: false),
+      FlutterVersion: () => stable,
     }));
   });
 }
 
+class MockFlutterVersion extends Mock implements FlutterVersion {
+  MockFlutterVersion(this.isStable);
+
+  final bool isStable;
+
+  @override
+  bool get isMaster => !isStable;
+}
+
 class MockProcessManager extends Mock implements ProcessManager {}
 
 class MockPlatform extends Mock implements Platform {
diff --git a/packages/flutter_tools/test/general.shard/windows/windows_workflow_test.dart b/packages/flutter_tools/test/general.shard/windows/windows_workflow_test.dart
index 86a566b..4c9d202 100644
--- a/packages/flutter_tools/test/general.shard/windows/windows_workflow_test.dart
+++ b/packages/flutter_tools/test/general.shard/windows/windows_workflow_test.dart
@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'package:flutter_tools/src/features.dart';
 import 'package:mockito/mockito.dart';
 
 import 'package:flutter_tools/src/base/platform.dart';
@@ -10,50 +9,36 @@
 
 import '../../src/common.dart';
 import '../../src/context.dart';
-import '../../src/testbed.dart';
 
 void main() {
-  Testbed testbed;
-  MockPlatform windows;
-  MockPlatform notWindows;
-
-  setUp(() {
-    windows = MockPlatform();
-    notWindows = MockPlatform();
+  group(WindowsWorkflow, () {
+    final MockPlatform windows = MockPlatform();
+    final MockPlatform windowsWithFde = MockPlatform()
+      ..environment['ENABLE_FLUTTER_DESKTOP'] = 'true';
+    final MockPlatform notWindows = MockPlatform();
     when(windows.isWindows).thenReturn(true);
+    when(windowsWithFde.isWindows).thenReturn(true);
     when(notWindows.isWindows).thenReturn(false);
-    testbed = Testbed(
-      overrides: <Type, Generator>{
-        Platform: () => windows,
-        FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: true),
-      }
-    );
+
+    testUsingContext('Applies to windows platform', () {
+      expect(windowsWorkflow.appliesToHostPlatform, true);
+    }, overrides: <Type, Generator>{
+      Platform: () => windows,
+    });
+    testUsingContext('Does not apply to non-windows platform', () {
+      expect(windowsWorkflow.appliesToHostPlatform, false);
+    }, overrides: <Type, Generator>{
+      Platform: () => notWindows,
+    });
+
+    testUsingContext('defaults', () {
+      expect(windowsWorkflow.canListEmulators, false);
+      expect(windowsWorkflow.canLaunchDevices, true);
+      expect(windowsWorkflow.canListDevices, true);
+    }, overrides: <Type, Generator>{
+      Platform: () => windowsWithFde,
+    });
   });
-
-  test('Windows default workflow values', () => testbed.run(() {
-    expect(windowsWorkflow.appliesToHostPlatform, true);
-    expect(windowsWorkflow.canListDevices, true);
-    expect(windowsWorkflow.canLaunchDevices, true);
-    expect(windowsWorkflow.canListEmulators, false);
-  }));
-
-  test('Windows defaults on non-windows platform', () => testbed.run(() {
-    expect(windowsWorkflow.appliesToHostPlatform, false);
-    expect(windowsWorkflow.canListDevices, false);
-    expect(windowsWorkflow.canLaunchDevices, false);
-    expect(windowsWorkflow.canListEmulators, false);
-  }, overrides: <Type, Generator>{
-    Platform: () => notWindows,
-  }));
-
-  test('Windows defaults on non-windows platform', () => testbed.run(() {
-    expect(windowsWorkflow.appliesToHostPlatform, false);
-    expect(windowsWorkflow.canListDevices, false);
-    expect(windowsWorkflow.canLaunchDevices, false);
-    expect(windowsWorkflow.canListEmulators, false);
-  }, overrides: <Type, Generator>{
-    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: false),
-  }));
 }
 
 class MockPlatform extends Mock implements Platform {
diff --git a/packages/flutter_tools/test/src/common.dart b/packages/flutter_tools/test/src/common.dart
index 3a3a4ea..2b8f22a 100644
--- a/packages/flutter_tools/test/src/common.dart
+++ b/packages/flutter_tools/test/src/common.dart
@@ -5,6 +5,8 @@
 import 'dart:async';
 
 import 'package:args/command_runner.dart';
+import 'package:flutter_tools/src/desktop.dart';
+import 'package:flutter_tools/src/web/workflow.dart';
 import 'package:test_api/test_api.dart' hide TypeMatcher, isInstanceOf;
 import 'package:test_api/test_api.dart' as test_package show TypeMatcher;
 
@@ -18,6 +20,19 @@
 
 export 'package:test_core/test_core.dart' hide TypeMatcher, isInstanceOf; // Defines a 'package:test' shim.
 
+/// Disable both web and desktop to make testing easier. For example, prevent
+/// them from showing up in the devices list if the host happens to be setup
+/// properly.
+set debugDisableWebAndDesktop(bool value) {
+  if (value) {
+    debugDisableDesktop = true;
+    debugDisableWeb = true;
+  } else {
+    debugDisableDesktop = false;
+    debugDisableWeb = false;
+  }
+}
+
 /// A matcher that compares the type of the actual value to the type argument T.
 // TODO(ianh): Remove this once https://github.com/dart-lang/matcher/issues/98 is fixed
 Matcher isInstanceOf<T>() => test_package.TypeMatcher<T>();
diff --git a/packages/flutter_tools/test/src/testbed.dart b/packages/flutter_tools/test/src/testbed.dart
index c0a6873..ac4901c 100644
--- a/packages/flutter_tools/test/src/testbed.dart
+++ b/packages/flutter_tools/test/src/testbed.dart
@@ -17,7 +17,6 @@
 import 'package:flutter_tools/src/base/terminal.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/context_runner.dart';
-import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/reporting/usage.dart';
 import 'package:flutter_tools/src/version.dart';
 
@@ -688,26 +687,3 @@
     return null;
   }
 }
-
-// A test implementation of [FeatureFlags] that allows enabling without reading
-// config. If not otherwise specified, all values default to false.
-class TestFeatureFlags implements FeatureFlags {
-  TestFeatureFlags({
-    this.isLinuxEnabled = false,
-    this.isMacOSEnabled = false,
-    this.isWebEnabled = false,
-    this.isWindowsEnabled = false,
-});
-
-  @override
-  final bool isLinuxEnabled;
-
-  @override
-  final bool isMacOSEnabled;
-
-  @override
-  final bool isWebEnabled;
-
-  @override
-  final bool isWindowsEnabled;
-}