[ES6 modules] Introduce ModuleScriptLoader

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

+// 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 ModuleScriptLoaderRegistry_h
+#define ModuleScriptLoaderRegistry_h
+
+#include "core/CoreExport.h"
+#include "platform/heap/Handle.h"
+#include "platform/weborigin/KURL.h"
+#include "wtf/HashSet.h"
+
+namespace blink {
+
+class Modulator;
+class ModuleScriptFetchRequest;
+class ModuleScriptLoader;
+class ModuleScriptLoaderClient;
+class ResourceFetcher;
+enum class ModuleGraphLevel;
+
+// ModuleScriptLoaderRegistry keeps active ModuleLoaders alive.
+class CORE_EXPORT ModuleScriptLoaderRegistry final
+    : public GarbageCollected<ModuleScriptLoaderRegistry> {
+ public:
+  static ModuleScriptLoaderRegistry* create() {
+    return new ModuleScriptLoaderRegistry;
+  }
+  DECLARE_TRACE();
+
+  ModuleScriptLoader* fetch(const ModuleScriptFetchRequest&,
+                            ModuleGraphLevel,
+                            Modulator*,
+                            ResourceFetcher*,
+                            ModuleScriptLoaderClient*);
+
+ private:
+  ModuleScriptLoaderRegistry() = default;
+
+  friend class ModuleScriptLoader;
+  void releaseFinishedLoader(ModuleScriptLoader*);
+
+  HeapHashSet<Member<ModuleScriptLoader>> m_activeLoaders;
+};
+
+}  // namespace blink
+
+#endif