[web:tools] always use CanvasKit from the cache when building web apps (#93002)

packages/flutter_tools/lib/src/build_system/targets/web.dart

@@ -410,9 +410,10 @@ class WebReleaseBundle extends Target {
 /// These assets can be cached forever and are only invalidated when the
 /// Flutter SDK is upgraded to a new version.
 class WebBuiltInAssets extends Target {
-  const WebBuiltInAssets(this.fileSystem);
+  const WebBuiltInAssets(this.fileSystem, this.cache);
 
   final FileSystem fileSystem;
+  final Cache cache;
 
   @override
   String get name => 'web_static_assets';
@@ -431,7 +432,15 @@ class WebBuiltInAssets extends Target {
 
   @override
   Future<void> build(Environment environment) async {
-    final Directory flutterWebSdk = globals.artifacts.getHostArtifact(HostArtifact.flutterWebSdk) as Directory;
+    // TODO(yjbanov): https://github.com/flutter/flutter/issues/52588
+    //
+    // Update this when we start building CanvasKit from sources. In the
+    // meantime, get the Web SDK directory from cache rather than through
+    // Artifacts. The latter is sensitive to `--local-engine`, which changes
+    // the directory to point to ENGINE/src/out. However, CanvasKit is not yet
+    // built as part of the engine, but fetched from CIPD, and so it won't be
+    // found in ENGINE/src/out.
+    final Directory flutterWebSdk = cache.getWebSdkDirectory();
     final Directory canvasKitDirectory = flutterWebSdk.childDirectory('canvaskit');
     for (final File file in canvasKitDirectory.listSync(recursive: true).whereType<File>()) {
       final String relativePath = fileSystem.path.relative(file.path, from: canvasKitDirectory.path);
@@ -443,9 +452,10 @@ class WebBuiltInAssets extends Target {
 
 /// Generate a service worker for a web target.
 class WebServiceWorker extends Target {
-  const WebServiceWorker(this.fileSystem);
+  const WebServiceWorker(this.fileSystem, this.cache);
 
   final FileSystem fileSystem;
+  final Cache cache;
 
   @override
   String get name => 'web_service_worker';
@@ -454,7 +464,7 @@ class WebServiceWorker extends Target {
   List<Target> get dependencies => <Target>[
     const Dart2JSTarget(),
     const WebReleaseBundle(),
-    WebBuiltInAssets(fileSystem),
+    WebBuiltInAssets(fileSystem, cache),
   ];
 
   @override

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

@@ -49,7 +49,7 @@ List<Target> _kDefaultTargets = <Target>[
   const ReleaseBundleLinuxAssets(TargetPlatform.linux_x64),
   const ReleaseBundleLinuxAssets(TargetPlatform.linux_arm64),
   // Web targets
-  WebServiceWorker(globals.fs),
+  WebServiceWorker(globals.fs, globals.cache),
   const ReleaseAndroidApplication(),
   // This is a one-off rule for bundle and aot compat.
   const CopyFlutterBundle(),

packages/flutter_tools/lib/src/web/compile.dart

@@ -37,7 +37,7 @@ Future<void> buildWeb(
   final Status status = globals.logger.startProgress('Compiling $target for the Web...');
   final Stopwatch sw = Stopwatch()..start();
   try {
-    final BuildResult result = await globals.buildSystem.build(WebServiceWorker(globals.fs), Environment(
+    final BuildResult result = await globals.buildSystem.build(WebServiceWorker(globals.fs, globals.cache), Environment(
       projectDir: globals.fs.currentDirectory,
       outputDir: outputDirectory,
       buildDir: flutterProject.directory

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

@@ -637,7 +637,7 @@ void main() {
     environment.outputDir.childDirectory('a').childFile('a.txt')
       ..createSync(recursive: true)
       ..writeAsStringSync('A');
-    await WebServiceWorker(globals.fs).build(environment);
+    await WebServiceWorker(globals.fs, globals.cache).build(environment);
 
     expect(environment.outputDir.childFile('flutter_service_worker.js'), exists);
     // Contains file hash.
@@ -656,7 +656,7 @@ void main() {
     environment.outputDir
       .childFile('index.html')
       .createSync(recursive: true);
-    await WebServiceWorker(globals.fs).build(environment);
+    await WebServiceWorker(globals.fs, globals.cache).build(environment);
 
     expect(environment.outputDir.childFile('flutter_service_worker.js'), exists);
     // Contains file hash for both `/` and index.html.
@@ -674,7 +674,7 @@ void main() {
     environment.outputDir
       .childFile('main.dart.js.map')
       .createSync(recursive: true);
-    await WebServiceWorker(globals.fs).build(environment);
+    await WebServiceWorker(globals.fs, globals.cache).build(environment);
 
     // No caching of source maps.
     expect(environment.outputDir.childFile('flutter_service_worker.js').readAsStringSync(),