Build devicelab iOS apps as universal binaries (#18102)

Eliminates 64-bit hardcoding for iOS test apps under dev/. This brings
them in line with the default iOS app templates.
diff --git a/dev/benchmarks/complex_layout/ios/Flutter/AppFrameworkInfo.plist b/dev/benchmarks/complex_layout/ios/Flutter/AppFrameworkInfo.plist
index 6c2de80..9367d48 100644
--- a/dev/benchmarks/complex_layout/ios/Flutter/AppFrameworkInfo.plist
+++ b/dev/benchmarks/complex_layout/ios/Flutter/AppFrameworkInfo.plist
@@ -20,10 +20,6 @@
   <string>????</string>
   <key>CFBundleVersion</key>
   <string>1.0</string>
-  <key>UIRequiredDeviceCapabilities</key>
-  <array>
-    <string>arm64</string>
-  </array>
   <key>MinimumOSVersion</key>
   <string>8.0</string>
 </dict>
diff --git a/dev/benchmarks/complex_layout/ios/Runner/Info.plist b/dev/benchmarks/complex_layout/ios/Runner/Info.plist
index d118951..81b3511 100644
--- a/dev/benchmarks/complex_layout/ios/Runner/Info.plist
+++ b/dev/benchmarks/complex_layout/ios/Runner/Info.plist
@@ -26,10 +26,6 @@
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>
 	<string>Main</string>
-	<key>UIRequiredDeviceCapabilities</key>
-	<array>
-		<string>arm64</string>
-	</array>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
diff --git a/dev/benchmarks/microbenchmarks/ios/Flutter/AppFrameworkInfo.plist b/dev/benchmarks/microbenchmarks/ios/Flutter/AppFrameworkInfo.plist
index 6c2de80..9367d48 100644
--- a/dev/benchmarks/microbenchmarks/ios/Flutter/AppFrameworkInfo.plist
+++ b/dev/benchmarks/microbenchmarks/ios/Flutter/AppFrameworkInfo.plist
@@ -20,10 +20,6 @@
   <string>????</string>
   <key>CFBundleVersion</key>
   <string>1.0</string>
-  <key>UIRequiredDeviceCapabilities</key>
-  <array>
-    <string>arm64</string>
-  </array>
   <key>MinimumOSVersion</key>
   <string>8.0</string>
 </dict>
diff --git a/dev/benchmarks/microbenchmarks/ios/Runner/Info.plist b/dev/benchmarks/microbenchmarks/ios/Runner/Info.plist
index 173a78b..f08ba2b 100644
--- a/dev/benchmarks/microbenchmarks/ios/Runner/Info.plist
+++ b/dev/benchmarks/microbenchmarks/ios/Runner/Info.plist
@@ -26,10 +26,6 @@
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>
 	<string>Main</string>
-	<key>UIRequiredDeviceCapabilities</key>
-	<array>
-		<string>arm64</string>
-	</array>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
diff --git a/dev/integration_tests/channels/ios/Flutter/AppFrameworkInfo.plist b/dev/integration_tests/channels/ios/Flutter/AppFrameworkInfo.plist
index 6c2de80..9367d48 100644
--- a/dev/integration_tests/channels/ios/Flutter/AppFrameworkInfo.plist
+++ b/dev/integration_tests/channels/ios/Flutter/AppFrameworkInfo.plist
@@ -20,10 +20,6 @@
   <string>????</string>
   <key>CFBundleVersion</key>
   <string>1.0</string>
-  <key>UIRequiredDeviceCapabilities</key>
-  <array>
-    <string>arm64</string>
-  </array>
   <key>MinimumOSVersion</key>
   <string>8.0</string>
 </dict>
diff --git a/dev/integration_tests/channels/ios/Runner.xcodeproj/project.pbxproj b/dev/integration_tests/channels/ios/Runner.xcodeproj/project.pbxproj
index 0084056..435e374 100644
--- a/dev/integration_tests/channels/ios/Runner.xcodeproj/project.pbxproj
+++ b/dev/integration_tests/channels/ios/Runner.xcodeproj/project.pbxproj
@@ -356,7 +356,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
@@ -378,7 +377,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
diff --git a/dev/integration_tests/channels/ios/Runner/Info.plist b/dev/integration_tests/channels/ios/Runner/Info.plist
index 04cb09d..1b72d9a 100644
--- a/dev/integration_tests/channels/ios/Runner/Info.plist
+++ b/dev/integration_tests/channels/ios/Runner/Info.plist
@@ -26,10 +26,6 @@
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>
 	<string>Main</string>
-	<key>UIRequiredDeviceCapabilities</key>
-	<array>
-		<string>arm64</string>
-	</array>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
diff --git a/dev/integration_tests/external_ui/ios/Flutter/AppFrameworkInfo.plist b/dev/integration_tests/external_ui/ios/Flutter/AppFrameworkInfo.plist
index 6c2de80..9367d48 100644
--- a/dev/integration_tests/external_ui/ios/Flutter/AppFrameworkInfo.plist
+++ b/dev/integration_tests/external_ui/ios/Flutter/AppFrameworkInfo.plist
@@ -20,10 +20,6 @@
   <string>????</string>
   <key>CFBundleVersion</key>
   <string>1.0</string>
-  <key>UIRequiredDeviceCapabilities</key>
-  <array>
-    <string>arm64</string>
-  </array>
   <key>MinimumOSVersion</key>
   <string>8.0</string>
 </dict>
diff --git a/dev/integration_tests/external_ui/ios/Runner.xcodeproj/project.pbxproj b/dev/integration_tests/external_ui/ios/Runner.xcodeproj/project.pbxproj
index 68f239e..a1db3c9 100644
--- a/dev/integration_tests/external_ui/ios/Runner.xcodeproj/project.pbxproj
+++ b/dev/integration_tests/external_ui/ios/Runner.xcodeproj/project.pbxproj
@@ -346,7 +346,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
@@ -368,7 +367,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
diff --git a/dev/integration_tests/external_ui/ios/Runner/Info.plist b/dev/integration_tests/external_ui/ios/Runner/Info.plist
index 2e5b6ec..7daee0e 100644
--- a/dev/integration_tests/external_ui/ios/Runner/Info.plist
+++ b/dev/integration_tests/external_ui/ios/Runner/Info.plist
@@ -26,10 +26,6 @@
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>
 	<string>Main</string>
-	<key>UIRequiredDeviceCapabilities</key>
-	<array>
-		<string>arm64</string>
-	</array>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
diff --git a/dev/integration_tests/flavors/ios/Flutter/AppFrameworkInfo.plist b/dev/integration_tests/flavors/ios/Flutter/AppFrameworkInfo.plist
index 6c2de80..9367d48 100644
--- a/dev/integration_tests/flavors/ios/Flutter/AppFrameworkInfo.plist
+++ b/dev/integration_tests/flavors/ios/Flutter/AppFrameworkInfo.plist
@@ -20,10 +20,6 @@
   <string>????</string>
   <key>CFBundleVersion</key>
   <string>1.0</string>
-  <key>UIRequiredDeviceCapabilities</key>
-  <array>
-    <string>arm64</string>
-  </array>
   <key>MinimumOSVersion</key>
   <string>8.0</string>
 </dict>
diff --git a/dev/integration_tests/flavors/ios/Runner.xcodeproj/project.pbxproj b/dev/integration_tests/flavors/ios/Runner.xcodeproj/project.pbxproj
index 7b1adb1..3d7e193 100644
--- a/dev/integration_tests/flavors/ios/Runner.xcodeproj/project.pbxproj
+++ b/dev/integration_tests/flavors/ios/Runner.xcodeproj/project.pbxproj
@@ -315,7 +315,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
@@ -380,7 +379,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
@@ -494,7 +492,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
@@ -516,7 +513,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
diff --git a/dev/integration_tests/flavors/ios/Runner/Info.plist b/dev/integration_tests/flavors/ios/Runner/Info.plist
index 7a6821f..57e8917 100644
--- a/dev/integration_tests/flavors/ios/Runner/Info.plist
+++ b/dev/integration_tests/flavors/ios/Runner/Info.plist
@@ -28,10 +28,6 @@
 	<string>Main</string>
   <key>Flavor</key>
   <string>${PRODUCT_FLAVOR}</string>
-	<key>UIRequiredDeviceCapabilities</key>
-	<array>
-		<string>arm64</string>
-	</array>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
diff --git a/dev/integration_tests/platform_interaction/ios/Flutter/AppFrameworkInfo.plist b/dev/integration_tests/platform_interaction/ios/Flutter/AppFrameworkInfo.plist
index 6c2de80..9367d48 100644
--- a/dev/integration_tests/platform_interaction/ios/Flutter/AppFrameworkInfo.plist
+++ b/dev/integration_tests/platform_interaction/ios/Flutter/AppFrameworkInfo.plist
@@ -20,10 +20,6 @@
   <string>????</string>
   <key>CFBundleVersion</key>
   <string>1.0</string>
-  <key>UIRequiredDeviceCapabilities</key>
-  <array>
-    <string>arm64</string>
-  </array>
   <key>MinimumOSVersion</key>
   <string>8.0</string>
 </dict>
diff --git a/dev/integration_tests/platform_interaction/ios/Runner.xcodeproj/project.pbxproj b/dev/integration_tests/platform_interaction/ios/Runner.xcodeproj/project.pbxproj
index 8fc33c3..b5a9e6e 100644
--- a/dev/integration_tests/platform_interaction/ios/Runner.xcodeproj/project.pbxproj
+++ b/dev/integration_tests/platform_interaction/ios/Runner.xcodeproj/project.pbxproj
@@ -362,7 +362,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
@@ -384,7 +383,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
diff --git a/dev/integration_tests/platform_interaction/ios/Runner/Info.plist b/dev/integration_tests/platform_interaction/ios/Runner/Info.plist
index 6efc899..4dbb731 100644
--- a/dev/integration_tests/platform_interaction/ios/Runner/Info.plist
+++ b/dev/integration_tests/platform_interaction/ios/Runner/Info.plist
@@ -26,10 +26,6 @@
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>
 	<string>Main</string>
-	<key>UIRequiredDeviceCapabilities</key>
-	<array>
-		<string>arm64</string>
-	</array>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
diff --git a/dev/integration_tests/ui/ios/Flutter/AppFrameworkInfo.plist b/dev/integration_tests/ui/ios/Flutter/AppFrameworkInfo.plist
index 6c2de80..9367d48 100644
--- a/dev/integration_tests/ui/ios/Flutter/AppFrameworkInfo.plist
+++ b/dev/integration_tests/ui/ios/Flutter/AppFrameworkInfo.plist
@@ -20,10 +20,6 @@
   <string>????</string>
   <key>CFBundleVersion</key>
   <string>1.0</string>
-  <key>UIRequiredDeviceCapabilities</key>
-  <array>
-    <string>arm64</string>
-  </array>
   <key>MinimumOSVersion</key>
   <string>8.0</string>
 </dict>
diff --git a/dev/integration_tests/ui/ios/Runner.xcodeproj/project.pbxproj b/dev/integration_tests/ui/ios/Runner.xcodeproj/project.pbxproj
index 34bfb89..ce82a64 100644
--- a/dev/integration_tests/ui/ios/Runner.xcodeproj/project.pbxproj
+++ b/dev/integration_tests/ui/ios/Runner.xcodeproj/project.pbxproj
@@ -360,7 +360,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
@@ -382,7 +381,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
diff --git a/dev/integration_tests/ui/ios/Runner/Info.plist b/dev/integration_tests/ui/ios/Runner/Info.plist
index 15b52b0..bc2cc31 100644
--- a/dev/integration_tests/ui/ios/Runner/Info.plist
+++ b/dev/integration_tests/ui/ios/Runner/Info.plist
@@ -26,10 +26,6 @@
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>
 	<string>Main</string>
-	<key>UIRequiredDeviceCapabilities</key>
-	<array>
-		<string>arm64</string>
-	</array>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>
diff --git a/dev/manual_tests/ios/Flutter/AppFrameworkInfo.plist b/dev/manual_tests/ios/Flutter/AppFrameworkInfo.plist
index 6c2de80..9367d48 100644
--- a/dev/manual_tests/ios/Flutter/AppFrameworkInfo.plist
+++ b/dev/manual_tests/ios/Flutter/AppFrameworkInfo.plist
@@ -20,10 +20,6 @@
   <string>????</string>
   <key>CFBundleVersion</key>
   <string>1.0</string>
-  <key>UIRequiredDeviceCapabilities</key>
-  <array>
-    <string>arm64</string>
-  </array>
   <key>MinimumOSVersion</key>
   <string>8.0</string>
 </dict>
diff --git a/dev/manual_tests/ios/Runner.xcodeproj/project.pbxproj b/dev/manual_tests/ios/Runner.xcodeproj/project.pbxproj
index 652d1e3..918b8f2 100644
--- a/dev/manual_tests/ios/Runner.xcodeproj/project.pbxproj
+++ b/dev/manual_tests/ios/Runner.xcodeproj/project.pbxproj
@@ -364,7 +364,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
@@ -386,7 +385,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ARCHS = arm64;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				ENABLE_BITCODE = NO;
 				FRAMEWORK_SEARCH_PATHS = (
diff --git a/dev/manual_tests/ios/Runner/Info.plist b/dev/manual_tests/ios/Runner/Info.plist
index 5776648..448f5cc 100644
--- a/dev/manual_tests/ios/Runner/Info.plist
+++ b/dev/manual_tests/ios/Runner/Info.plist
@@ -26,10 +26,6 @@
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>
 	<string>Main</string>
-	<key>UIRequiredDeviceCapabilities</key>
-	<array>
-		<string>arm64</string>
-	</array>
 	<key>UISupportedInterfaceOrientations</key>
 	<array>
 		<string>UIInterfaceOrientationPortrait</string>