flutter build aar regenerates tooling between each build-mode step (#162705)

Closes flutter/flutter#162703.

I still need to do a similar change for `ios|macos`-`framework` in
flutter/flutter#162704.

I added two unit tests, as well as opted in an integration test to the
flag (it will become the default in
flutter/flutter#160289).

/cc @reidbaker @gmackall.

Author: matanlurey

dev/devicelab/bin/tasks/build_aar_module_test.dart

@@ -21,6 +21,11 @@ Future<void> main() async {
     }
     print('\nUsing JAVA_HOME=$javaHome');
 
+    // TODO(matanlurey): Remove after default.
+    // https://github.com/flutter/flutter/issues/160257
+    section('Opt-in to --explicit-package-dependencies');
+    await flutter('config', options: <String>['--explicit-package-dependencies']);
+
     final Directory tempDir = Directory.systemTemp.createTempSync('flutter_module_test.');
     final Directory projectDir = Directory(path.join(tempDir.path, 'hello'));
     try {

packages/flutter_tools/lib/src/android/android_builder.dart

@@ -19,6 +19,7 @@ abstract class AndroidBuilder {
     required FlutterProject project,
     required Set<AndroidBuildInfo> androidBuildInfo,
     required String target,
+    required Future<void> Function(FlutterProject, {required bool releaseMode}) generateTooling,
     String? outputDirectoryPath,
     required String buildNumber,
   });

packages/flutter_tools/lib/src/android/gradle.dart

@@ -191,6 +191,7 @@ class AndroidGradleBuilder implements AndroidBuilder {
     required FlutterProject project,
     required Set<AndroidBuildInfo> androidBuildInfo,
     required String target,
+    required Future<void> Function(FlutterProject, {required bool releaseMode}) generateTooling,
     String? outputDirectoryPath,
     required String buildNumber,
   }) async {
@@ -208,6 +209,7 @@ class AndroidGradleBuilder implements AndroidBuilder {
       _logger.printWarning(androidX86DeprecationWarning);
     }
     for (final AndroidBuildInfo androidBuildInfo in androidBuildInfo) {
+      await generateTooling(project, releaseMode: androidBuildInfo.buildInfo.isRelease);
       await buildGradleAar(
         project: project,
         androidBuildInfo: androidBuildInfo,

packages/flutter_tools/lib/src/commands/build_aar.dart

@@ -111,6 +111,9 @@ class BuildAarCommand extends BuildSubCommand {
     await super.validateCommand();
   }
 
+  @override
+  bool get regeneratePlatformSpecificToolingDurifyVerify => false;
+
   @override
   Future<FlutterCommandResult> runCommand() async {
     if (_androidSdk == null) {
@@ -149,10 +152,12 @@ class BuildAarCommand extends BuildSubCommand {
     }
 
     displayNullSafetyMode(androidBuildInfo.first.buildInfo);
+
     await androidBuilder?.buildAar(
       project: project,
       target: targetFile.path,
       androidBuildInfo: androidBuildInfo,
+      generateTooling: regeneratePlatformSpecificToolingIfApplicable,
       outputDirectoryPath: stringArg('output'),
       buildNumber: buildNumber,
     );

packages/flutter_tools/lib/src/runner/flutter_command.dart

@@ -1893,22 +1893,15 @@ Run 'flutter -h' (or 'flutter <command> -h') for available flutter commands and
         buildSystem: globals.buildSystem,
         buildTargets: globals.buildTargets,
       );
-
-      // null implicitly means all plugins are allowed
-      List<String>? allowedPlugins;
-      if (stringArg(FlutterGlobalOptions.kDeviceIdOption, global: true) == 'preview') {
-        // The preview device does not currently support any plugins.
-        allowedPlugins = PreviewDevice.supportedPubPlugins;
-      }
-      await project.regeneratePlatformSpecificTooling(
-        allowedPlugins: allowedPlugins,
-        releaseMode: featureFlags.isExplicitPackageDependenciesEnabled && getBuildMode().isRelease,
-      );
       if (reportNullSafety) {
         await _sendNullSafetyAnalyticsEvents(project);
       }
     }
 
+    if (regeneratePlatformSpecificToolingDurifyVerify) {
+      await regeneratePlatformSpecificToolingIfApplicable(project);
+    }
+
     setupApplicationPackages();
 
     if (commandPath != null) {
@@ -1918,6 +1911,66 @@ Run 'flutter -h' (or 'flutter <command> -h') for available flutter commands and
     return runCommand();
   }
 
+  /// Whether to run [regeneratePlatformSpecificTooling] in [verifyThenRunCommand].
+  ///
+  /// By default `true`, but sub-commands that do _meta_ builds (make multiple different
+  /// builds sequentially in one-go) may choose to override this and provide `false`, instead
+  /// calling [regeneratePlatformSpecificTooling] manually when applicable.
+  @visibleForOverriding
+  bool get regeneratePlatformSpecificToolingDurifyVerify => true;
+
+  /// Runs [FlutterProject.regeneratePlatformSpecificTooling] for [project] with appropriate configuration.
+  ///
+  /// By default, this uses [getBuildMode] to determine and provide whether a release build is being made,
+  /// but sub-commands (such as commands that do _meta_ builds, or builds that make multiple different builds
+  /// sequentially in one-go) may choose to overide this and make the call at a different point in time.
+  ///
+  /// This method should only be called when [shouldRunPub] is `true`:
+  /// ```dart
+  /// if (shouldRunPub) {
+  ///   await regeneratePlatformSpecificTooling(project);
+  /// }
+  /// ```
+  ///
+  /// See also:
+  ///
+  /// - <https://github.com/flutter/flutter/issues/162649>.
+  @protected
+  @nonVirtual
+  Future<void> regeneratePlatformSpecificToolingIfApplicable(
+    FlutterProject project, {
+    bool? releaseMode,
+  }) async {
+    if (!shouldRunPub) {
+      return;
+    }
+
+    // TODO(matanlurey): Determine if PreviewDevice should be kept.
+    // https://github.com/flutter/flutter/issues/162693
+    final List<String>? allowedPlugins;
+    if (stringArg(FlutterGlobalOptions.kDeviceIdOption, global: true) == 'preview') {
+      // The preview device does not currently support any plugins.
+      allowedPlugins = PreviewDevice.supportedPubPlugins;
+    } else {
+      // null means all plugins are allowed
+      allowedPlugins = null;
+    }
+
+    await project.regeneratePlatformSpecificTooling(
+      allowedPlugins: allowedPlugins,
+      // TODO(matanlurey): Move this up, i.e. releaseMode ??= getBuildMode().release.
+      //
+      // As it stands, this is a breaking change until https://github.com/flutter/flutter/issues/162704 is
+      // implemented, as the build_ios_framework command (and similar) will start querying
+      // for getBuildMode(), causing an error (meta-build commands like build ios-framework do not have
+      // a single build mode). Once ios-framework and macos-framework are migrated, then this can be
+      // cleaned up.
+      releaseMode:
+          featureFlags.isExplicitPackageDependenciesEnabled &&
+          (releaseMode ?? getBuildMode().isRelease),
+    );
+  }
+
   Future<void> _sendNullSafetyAnalyticsEvents(FlutterProject project) async {
     final BuildInfo buildInfo = await getBuildInfo();
     NullSafetyAnalysisEvent(