MSE: Implement TrackDefaultList object

Source/modules/mediasource/TrackDefaultList.h

+// Copyright 2014 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 TrackDefaultList_h
+#define TrackDefaultList_h
+
+#include "bindings/core/v8/ScriptWrappable.h"
+#include "modules/mediasource/TrackDefault.h"
+#include "platform/heap/Handle.h"
+#include "wtf/text/AtomicStringHash.h"
+#include "wtf/text/StringHash.h"
+
+namespace blink {
+
+class ExceptionState;
+
+class TrackDefaultList final : public GarbageCollectedFinalized<TrackDefaultList>, public ScriptWrappable {

[sof, 2014/12/03 19:15:40]

This can be a non-finalized class; have it derive from
GarbageCollected<TraceDefaultList> instead + remove the dtor below.

[wolenetz, 2014/12/11 23:52:39]

Done.

+    DEFINE_WRAPPERTYPEINFO();
+public:
+    static TrackDefaultList* create(const HeapVector<Member<TrackDefault>>& trackDefaults, ExceptionState& exceptionState)
+    {
+        return new TrackDefaultList(trackDefaults, exceptionState);
+    }
+
+    virtual ~TrackDefaultList() { }
+
+    // Implement the IDL
+    unsigned length() const { return m_trackDefaults.size(); }
+    TrackDefault* item(unsigned) const;
+
+    void trace(Visitor*);
+
+private:
+    TrackDefaultList(const HeapVector<Member<TrackDefault>>&, ExceptionState&);
+
+    HeapVector<Member<TrackDefault>> m_trackDefaults;
+
+    // HashMapped index of |m_trackDefaults| for lookup by unique <type,
+    // byteStreamTrackID>.
+    typedef std::pair<AtomicString, String> TypeAndID;
+    typedef HeapHashMap<TypeAndID, Member<TrackDefault>> TypeAndIDToTrackDefaultMap;
+    TypeAndIDToTrackDefaultMap m_typeAndIDToTrackDefaultMap;
+};
+
+} // namespace blink
+
+#endif // TrackDefaultList_h