Start using bin/cache/engine.{stamp|realm} instead of bin/internal/engine.{realm|version}. (#164352)

Towards https://github.com/flutter/flutter/issues/164315.

See also:
https://github.com/flutter/flutter/blob/master/docs/tool/Engine-artifacts.md.

There are more usages in `flutter/flutter`, but some will require more
specialized review (i.e. from release folks, or the Dart SDK team), so
I'll split those off.

~~Requires https://github.com/flutter/flutter/pull/164317 to merge
first.~~ ✅

dev/bots/suite_runners/run_test_harness_tests.dart

@@ -133,8 +133,7 @@ Future<void> testHarnessTestsRunner() async {
   }
 }
 
-/// Verify the Flutter Engine is the revision in
-/// bin/cache/internal/engine.version.
+/// Verify the Flutter Engine is the revision in `bin/cache/engine.stamp`.
 Future<void> _validateEngineHash() async {
   final String flutterTester = path.join(
     flutterRoot,
@@ -146,6 +145,7 @@ Future<void> _validateEngineHash() async {
     'flutter_tester$exe',
   );
 
+  // TODO(matanlurey): Revisit with the Dart team if this is true now that they use FLUTTER_PREBUILT_ENGINE_VERSION=...
   if (runningInDartHHHBot) {
     // The Dart HHH bots intentionally modify the local artifact cache
     // and then use this script to run Flutter's test suites.

dev/bots/suite_runners/run_web_tests.dart

@@ -91,8 +91,8 @@ class WebTestsSuite {
 
   /// Coarse-grained integration tests running on the Web.
   Future<void> webLongRunningTestsRunner() async {
-    final String engineVersionFile = path.join(flutterRoot, 'bin', 'internal', 'engine.version');
-    final String engineRealmFile = path.join(flutterRoot, 'bin', 'internal', 'engine.realm');
+    final String engineVersionFile = path.join(flutterRoot, 'bin', 'cache', 'engine.stamp');
+    final String engineRealmFile = path.join(flutterRoot, 'bin', 'cache', 'engine.realm');
     final String engineVersion = File(engineVersionFile).readAsStringSync().trim();
     final String engineRealm = File(engineRealmFile).readAsStringSync().trim();
     if (engineRealm.isNotEmpty) {

dev/bots/utils.dart

@@ -61,7 +61,7 @@ final String flutterRoot = path.dirname(path.dirname(path.dirname(path.fromUri(P
 final String flutter = path.join(flutterRoot, 'bin', 'flutter$bat');
 final String dart = path.join(flutterRoot, 'bin', 'cache', 'dart-sdk', 'bin', 'dart$exe');
 final String pubCache = path.join(flutterRoot, '.pub-cache');
-final String engineVersionFile = path.join(flutterRoot, 'bin', 'internal', 'engine.version');
+final String engineVersionFile = path.join(flutterRoot, 'bin', 'cache', 'engine.stamp');
 final String luciBotId = Platform.environment['SWARMING_BOT_ID'] ?? '';
 final bool runningInDartHHHBot =
     luciBotId.startsWith('luci-dart-') || luciBotId.startsWith('dart-tests-');

dev/devicelab/bin/tasks/engine_dependency_proxy_test.dart

@@ -59,7 +59,7 @@ tasks.register("printEngineMavenUrl") {
 
         String realm =
             File(
-              path.join(flutterDirectory.path, 'bin', 'internal', 'engine.realm'),
+              path.join(flutterDirectory.path, 'bin', 'cache', 'engine.realm'),
             ).readAsStringSync().trim();
         if (realm.isNotEmpty) {
           realm = '$realm/';

dev/tools/create_api_docs.dart

@@ -1265,7 +1265,7 @@ class FlutterInformation {
     info['engineRevision'] = flutterVersion['engineRevision'] as String;
     final File engineRealm = flutterRoot
         .childDirectory('bin')
-        .childDirectory('internal')
+        .childDirectory('cache')
         .childFile('engine.realm');
     info['engineRealm'] = engineRealm.existsSync() ? engineRealm.readAsStringSync().trim() : '';
 

dev/tools/find_engine_commit.dart

@@ -6,7 +6,7 @@ import 'dart:io';
 
 void _validate(List<String> args) {
   bool errors = false;
-  if (!File('bin/internal/engine.version').existsSync()) {
+  if (!File('bin/cache/engine.stamp').existsSync()) {
     errors = true;
     print('This program must be run from the root of your flutter repository.');
   }

dev/tools/test/create_api_docs_test.dart

@@ -197,7 +197,7 @@ void main() {
           .childDirectory('user')
           .childDirectory('flutter')
           .childDirectory('bin')
-          .childDirectory('internal');
+          .childDirectory('cache');
       flutterHome.childFile('engine.realm')
         ..createSync(recursive: true)
         ..writeAsStringSync('realm');