Add builders and engine hash to fingerprint (#29434)

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

@@ -12,10 +12,12 @@ import '../android/android_sdk.dart';
 import '../artifacts.dart';
 import '../build_info.dart';
 import '../bundle.dart';
+import '../cache.dart';
 import '../compile.dart';
 import '../dart/package_map.dart';
 import '../globals.dart';
 import '../ios/mac.dart';
+import '../project.dart';
 import 'context.dart';
 import 'file_system.dart';
 import 'fingerprint.dart';
@@ -79,6 +81,11 @@ class AOTSnapshotter {
     IOSArch iosArch,
     List<String> extraGenSnapshotOptions = const <String>[],
   }) async {
+    FlutterProject flutterProject;
+    if (fs.file('pubspec.yaml').existsSync()) {
+      flutterProject = await FlutterProject.current();
+    }
+    final FlutterEngine engine = FlutterEngine(cache);
     if (!_isValidAotPlatform(platform, buildMode)) {
       printError('${getNameForTargetPlatform(platform)} does not support AOT compilation.');
       return 1;
@@ -180,6 +187,8 @@ class AOTSnapshotter {
         'entryPoint': mainPath,
         'sharedLib': buildSharedLibrary.toString(),
         'extraGenSnapshotOptions': extraGenSnapshotOptions.join(' '),
+        'engineHash': engine.version,
+        'buildersUsed': '${flutterProject != null ? await flutterProject.hasBuilders : false}',
       },
       depfilePaths: <String>[],
     );

packages/flutter_tools/lib/src/codegen.dart

@@ -148,8 +148,7 @@ class CodeGeneratingKernelCompiler implements KernelCompiler {
       fileSystemScheme: kMultiRootScheme,
       depFilePath: depFilePath,
       targetModel: targetModel,
-      // Pass an invalid file name to prevent frontend_server from initializing from dill.
-      initializeFromDill: 'none_file',
+      initializeFromDill: initializeFromDill,
     );
   }
 }
@@ -185,8 +184,7 @@ class CodeGeneratingResidentCompiler implements ResidentCompiler {
       fileSystemScheme: kMultiRootScheme,
       targetModel: TargetModel.flutter,
       unsafePackageSerialization: unsafePackageSerialization,
-      // Pass an invalid file name to prevent frontend_server from initializing from dill.
-      initializeFromDill: 'none_file',
+      initializeFromDill: initializeFromDill,
     );
     if (runCold) {
       return residentCompiler;

packages/flutter_tools/lib/src/compile.dart

@@ -16,9 +16,11 @@ import 'base/io.dart';
 import 'base/platform.dart';
 import 'base/process_manager.dart';
 import 'base/terminal.dart';
+import 'cache.dart';
 import 'convert.dart';
 import 'dart/package_map.dart';
 import 'globals.dart';
+import 'project.dart';
 
 KernelCompiler get kernelCompiler => context[KernelCompiler];
 
@@ -214,6 +216,11 @@ class KernelCompiler {
     final String frontendServer = artifacts.getArtifactPath(
       Artifact.frontendServerSnapshotForEngineDartSdk
     );
+    FlutterProject flutterProject;
+    if (fs.file('pubspec.yaml').existsSync()) {
+      flutterProject = await FlutterProject.current();
+    }
+    final FlutterEngine engine = FlutterEngine(cache);
 
     // TODO(cbracken): eliminate pathFilter.
     // Currently the compiler emits buildbot paths for the core libs in the
@@ -227,6 +234,8 @@ class KernelCompiler {
           'entryPoint': mainPath,
           'trackWidgetCreation': trackWidgetCreation.toString(),
           'linkPlatformKernelIn': linkPlatformKernelIn.toString(),
+          'engineHash': engine.version,
+          'buildersUsed': '${flutterProject != null ? await flutterProject.hasBuilders : false}',
         },
         depfilePaths: <String>[depFilePath],
         pathFilter: (String path) => !path.startsWith('/b/build/slave/'),