Revert "Warn when building on master channel (#25007)" (#27096)

This reverts commit dd65a54628159af18c0ab04d4868456526fa91e5.
diff --git a/packages/flutter_tools/lib/src/commands/build.dart b/packages/flutter_tools/lib/src/commands/build.dart
index 6386200..c31f741 100644
--- a/packages/flutter_tools/lib/src/commands/build.dart
+++ b/packages/flutter_tools/lib/src/commands/build.dart
@@ -4,13 +4,7 @@
 
 import 'dart:async';
 
-import 'package:meta/meta.dart';
-
-import '../base/terminal.dart';
-import '../globals.dart';
 import '../runner/flutter_command.dart';
-import '../version.dart';
-
 import 'build_aot.dart';
 import 'build_apk.dart';
 import 'build_appbundle.dart';
@@ -42,16 +36,4 @@
   BuildSubCommand() {
     requiresPubspecYaml();
   }
-
-  @override
-  @mustCallSuper
-  Future<FlutterCommandResult> runCommand() async {
-    // Warn if building a release app on Master channel
-    final String channel = FlutterVersion.instance.channel;
-    if (channel == 'master') {
-      printStatus('🐉', newline: false, color: TerminalColor.red);
-      printStatus(' This is the $channel channel. Shipping apps from this channel is not recommended as it has not been as heavily tested as the stable channel. To build using the stable channel, consider using:\n    flutter channel stable');
-    }
-    return null;
-  }
 }
diff --git a/packages/flutter_tools/lib/src/commands/build_aot.dart b/packages/flutter_tools/lib/src/commands/build_aot.dart
index fa98f4e..f541aae 100644
--- a/packages/flutter_tools/lib/src/commands/build_aot.dart
+++ b/packages/flutter_tools/lib/src/commands/build_aot.dart
@@ -57,8 +57,6 @@
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    await super.runCommand();
-
     final String targetPlatform = argResults['target-platform'];
     final TargetPlatform platform = getTargetPlatformForName(targetPlatform);
     if (platform == null)
diff --git a/packages/flutter_tools/lib/src/commands/build_apk.dart b/packages/flutter_tools/lib/src/commands/build_apk.dart
index 02eca5f..2660932 100644
--- a/packages/flutter_tools/lib/src/commands/build_apk.dart
+++ b/packages/flutter_tools/lib/src/commands/build_apk.dart
@@ -42,8 +42,6 @@
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    await super.runCommand();
-
     await buildApk(
       project: await FlutterProject.current(),
       target: targetFile,
diff --git a/packages/flutter_tools/lib/src/commands/build_appbundle.dart b/packages/flutter_tools/lib/src/commands/build_appbundle.dart
index 7fb45f3..bf8979a 100644
--- a/packages/flutter_tools/lib/src/commands/build_appbundle.dart
+++ b/packages/flutter_tools/lib/src/commands/build_appbundle.dart
@@ -40,8 +40,6 @@
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    await super.runCommand();
-
     await buildAppBundle(
       project: await FlutterProject.current(),
       target: targetFile,
diff --git a/packages/flutter_tools/lib/src/commands/build_bundle.dart b/packages/flutter_tools/lib/src/commands/build_bundle.dart
index 4093787..2fff12f 100644
--- a/packages/flutter_tools/lib/src/commands/build_bundle.dart
+++ b/packages/flutter_tools/lib/src/commands/build_bundle.dart
@@ -65,8 +65,6 @@
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    await super.runCommand();
-
     final String targetPlatform = argResults['target-platform'];
     final TargetPlatform platform = getTargetPlatformForName(targetPlatform);
     if (platform == null)
diff --git a/packages/flutter_tools/lib/src/commands/build_flx.dart b/packages/flutter_tools/lib/src/commands/build_flx.dart
index 4b0b3a1..d6a2274 100644
--- a/packages/flutter_tools/lib/src/commands/build_flx.dart
+++ b/packages/flutter_tools/lib/src/commands/build_flx.dart
@@ -20,8 +20,6 @@
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    await super.runCommand();
-
     printError("'build flx' is no longer supported. Instead, use 'build "
                "bundle' to build and assemble the application code and resources "
                'for your app.');
diff --git a/packages/flutter_tools/lib/src/commands/build_ios.dart b/packages/flutter_tools/lib/src/commands/build_ios.dart
index 77f8a01..b90e332 100644
--- a/packages/flutter_tools/lib/src/commands/build_ios.dart
+++ b/packages/flutter_tools/lib/src/commands/build_ios.dart
@@ -50,8 +50,6 @@
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    await super.runCommand();
-
     final bool forSimulator = argResults['simulator'];
     defaultBuildMode = forSimulator ? BuildMode.debug : BuildMode.release;
 
diff --git a/packages/flutter_tools/test/commands/build_test.dart b/packages/flutter_tools/test/commands/build_test.dart
deleted file mode 100644
index beb60f4..0000000
--- a/packages/flutter_tools/test/commands/build_test.dart
+++ /dev/null
@@ -1,93 +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 'dart:async';
-
-import 'package:flutter_tools/src/base/context.dart';
-import 'package:flutter_tools/src/commands/build.dart';
-import 'package:flutter_tools/src/cache.dart';
-import 'package:flutter_tools/src/version.dart';
-import 'package:flutter_tools/src/runner/flutter_command.dart';
-
-import '../src/common.dart';
-import '../src/context.dart';
-
-
-void main() {
-  group('Master channel warning', () {
-    testUsingContext('warns on master', () async {
-      final MockBuildCommand buildCommand = MockBuildCommand();
-      try {
-        await createTestCommandRunner(buildCommand).run(<String>['build', 'test']);
-      } finally {}
-      Cache.releaseLockEarly();
-      expect(testLogger.statusText, contains('🐉 This is the master channel. Shipping apps from this channel is not recommended as it has not'));
-    }, overrides: <Type, Generator>{
-      FlutterVersion: () => MockVersion('master'),
-    });
-
-    testUsingContext('no warning on stable', () async {
-      final MockBuildCommand buildCommand = MockBuildCommand();
-      try {
-        await createTestCommandRunner(buildCommand).run(<String>['build', 'test']);
-      } finally {}
-      Cache.releaseLockEarly();
-      expect(testLogger.statusText, '');
-    }, overrides: <Type, Generator>{
-      FlutterVersion: () => MockVersion('stable'),
-    });
-
-    testUsingContext('no warning on dev', () async {
-      final MockBuildCommand buildCommand = MockBuildCommand();
-      try {
-        await createTestCommandRunner(buildCommand).run(<String>['build', 'test']);
-      } finally {}
-      Cache.releaseLockEarly();
-      expect(testLogger.statusText, '');
-    }, overrides: <Type, Generator>{
-      FlutterVersion: () => MockVersion('dev'),
-    });
-
-    testUsingContext('no warning on beta', () async {
-      final MockBuildCommand buildCommand = MockBuildCommand();
-      try {
-        await createTestCommandRunner(buildCommand).run(<String>['build', 'test']);
-      } finally {}
-      print(testLogger.statusText);
-      Cache.releaseLockEarly();
-      expect(testLogger.statusText, '');
-    }, overrides: <Type, Generator>{
-      FlutterVersion: () => MockVersion('beta'),
-    });
-  });
-}
-
-class MockVersion extends FlutterVersion {
-  MockVersion(String channel) : _fakeChannel = channel;
-  String _fakeChannel;
-
-  @override
-  String get channel => _fakeChannel;
-}
-
-class MockBuildCommand extends BuildCommand {
-  MockBuildCommand() {
-    addSubcommand(MockBuildTestCommand());
-  }
-}
-
-// Avoids command validation
-class MockBuildTestCommand extends BuildSubCommand {
-  @override
-  final String name = 'test';
-
-  @override
-  final String description = 'This is a test class only.';
-
-  @override
-  Future<FlutterCommandResult> runCommand() async {
-    await super.runCommand();
-    return null;
-  }
-}