[POC] Implement "module responses map" concept

third_party/WebKit/Source/core/loader/modulescript/WorkletModuleScriptFetcher.h

Index: third_party/WebKit/Source/core/loader/modulescript/WorkletModuleScriptFetcher.h
diff --git a/third_party/WebKit/Source/core/loader/modulescript/WorkletModuleScriptFetcher.h b/third_party/WebKit/Source/core/loader/modulescript/WorkletModuleScriptFetcher.h
new file mode 100644
index 0000000000000000000000000000000000000000..476fa93924748b81f101bbcf61899ed839b94f87
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+++ b/third_party/WebKit/Source/core/loader/modulescript/WorkletModuleScriptFetcher.h
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+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef WorkletModuleScriptFetcher_h
+#define WorkletModuleScriptFetcher_h
+
+#include "core/loader/modulescript/ModuleScriptFetcher.h"
+
+#include "core/workers/WorkletModuleResponsesMap.h"
+#include "core/workers/WorkletModuleResponsesMapProxy.h"
+#include "platform/wtf/Optional.h"
+
+namespace blink {
+
+class WorkletModuleScriptFetcher final
+    : public ModuleScriptFetcher,
+      public WorkletModuleResponsesMap::Client {
+  USING_GARBAGE_COLLECTED_MIXIN(WorkletModuleScriptFetcher);
+
+ public:
+  CORE_EXPORT WorkletModuleScriptFetcher(FetchParameters,
+                                         ResourceFetcher*,
+                                         Modulator*,
+                                         WorkletModuleResponsesMapProxy*);
+
+  // Implements WorkletModuleResponsesMap::Client.
+  void OnRead(const ModuleScriptCreationParams&) override;
+  void OnFetchNeeded() override;
+  void OnFailed() override;
+
+  DECLARE_TRACE();
+
+ private:
+  void FetchInternal() override;
+
+  void Finalize(WTF::Optional<ModuleScriptCreationParams>) override;
+
+  Member<WorkletModuleResponsesMapProxy> module_responses_map_proxy_;
+  bool was_fetched_via_network_ = false;
+};
+
+}  // namespace blink
+
+#endif  // WorkletModuleScriptFetcher_h