Add support for producing unstripped AOT snapshots. (#75243)

packages/flutter_tools/lib/src/base/build.dart

@@ -137,9 +137,20 @@ class AOTSnapshotter {
     final List<String> genSnapshotArgs = <String>[
       '--deterministic',
     ];
+
+    // We strip snapshot by default, but allow to suppress this behavior
+    // by supplying --no-strip in extraGenSnapshotOptions.
+    bool shouldStrip = true;
+
     if (extraGenSnapshotOptions != null && extraGenSnapshotOptions.isNotEmpty) {
       _logger.printTrace('Extra gen_snapshot options: $extraGenSnapshotOptions');
-      genSnapshotArgs.addAll(extraGenSnapshotOptions);
+      for (final String option in extraGenSnapshotOptions) {
+        if (option == '--no-strip') {
+          shouldStrip = false;
+          continue;
+        }
+        genSnapshotArgs.add(option);
+      }
     }
 
     final String assembly = _fileSystem.path.join(outputDir.path, 'snapshot_assembly.S');
@@ -147,17 +158,19 @@ class AOTSnapshotter {
       genSnapshotArgs.addAll(<String>[
         '--snapshot_kind=app-aot-assembly',
         '--assembly=$assembly',
-        '--strip'
       ]);
     } else {
       final String aotSharedLibrary = _fileSystem.path.join(outputDir.path, 'app.so');
       genSnapshotArgs.addAll(<String>[
         '--snapshot_kind=app-aot-elf',
         '--elf=$aotSharedLibrary',
-        '--strip'
       ]);
     }
 
+    if (shouldStrip) {
+      genSnapshotArgs.add('--strip');
+    }
+
     if (platform == TargetPlatform.android_arm || darwinArch == DarwinArch.armv7) {
       // Use softfp for Android armv7 devices.
       // This is the default for armv7 iOS builds, but harmless to set.

packages/flutter_tools/test/general.shard/base/build_test.dart

@@ -666,5 +666,32 @@ void main() {
       expect(genSnapshotExitCode, 0);
       expect(processManager.hasRemainingExpectations, false);
     });
+
+    testWithoutContext('--no-strip in extraGenSnapshotOptions suppresses --strip', () async {
+      final String outputPath = fileSystem.path.join('build', 'foo');
+      processManager.addCommand(FakeCommand(
+        command: <String>[
+          artifacts.getArtifactPath(Artifact.genSnapshot, platform: TargetPlatform.android_arm64, mode: BuildMode.release),
+          '--deterministic',
+          '--snapshot_kind=app-aot-elf',
+          '--elf=build/foo/app.so',
+          'main.dill',
+        ]
+      ));
+
+      final int genSnapshotExitCode = await snapshotter.build(
+        platform: TargetPlatform.android_arm64,
+        buildMode: BuildMode.release,
+        mainPath: 'main.dill',
+        outputPath: outputPath,
+        bitcode: false,
+        splitDebugInfo: null,
+        dartObfuscation: false,
+        extraGenSnapshotOptions: const <String>['--no-strip'],
+      );
+
+      expect(genSnapshotExitCode, 0);
+      expect(processManager.hasRemainingExpectations, false);
+    });
   });
 }

packages/flutter_tools/test/general.shard/build_system/targets/android_test.dart

@@ -294,6 +294,47 @@ void main() {
     ProcessManager: () => processManager,
   });
 
+  testUsingContext('--no-strip in kExtraGenSnapshotOptions suppresses --strip gen_snapshot flag', () async {
+    processManager = FakeProcessManager.list(<FakeCommand>[]);
+    final Environment environment = Environment.test(
+      fileSystem.currentDirectory,
+      outputDir: fileSystem.directory('out')..createSync(),
+      defines: <String, String>{
+        kBuildMode: 'release',
+        kExtraGenSnapshotOptions: 'foo,--no-strip,bar',
+        kTargetPlatform: 'android-arm',
+      },
+      processManager: processManager,
+      artifacts: artifacts,
+      fileSystem: fileSystem,
+      logger: logger,
+    );
+    processManager.addCommand(
+      FakeCommand(command: <String>[
+        artifacts.getArtifactPath(
+          Artifact.genSnapshot,
+          platform: TargetPlatform.android_arm64,
+          mode: BuildMode.release,
+        ),
+        '--deterministic',
+        'foo',
+        'bar',
+        '--snapshot_kind=app-aot-elf',
+        '--elf=${environment.buildDir.childDirectory('arm64-v8a').childFile('app.so').path}',
+        environment.buildDir.childFile('app.dill').path
+      ],
+    ));
+    environment.buildDir.createSync(recursive: true);
+    environment.buildDir.childFile('app.dill').createSync();
+    environment.projectDir.childFile('.packages').writeAsStringSync('\n');
+
+    await const AndroidAot(TargetPlatform.android_arm64, BuildMode.release)
+      .build(environment);
+  }, overrides: <Type, Generator>{
+    FileSystem: () => fileSystem,
+    ProcessManager: () => processManager,
+  });
+
   testWithoutContext('android aot bundle copies so from abi directory', () async {
     final Environment environment = Environment.test(
       fileSystem.currentDirectory,