Basic use implementation for MediaStream from Canvas: captureStream()

third_party/WebKit/Source/core/html/HTMLCanvasElement.h

Index: third_party/WebKit/Source/core/html/HTMLCanvasElement.h
diff --git a/third_party/WebKit/Source/core/html/HTMLCanvasElement.h b/third_party/WebKit/Source/core/html/HTMLCanvasElement.h
index a8fdc1741b6ca79c51d50ab82c3b04d7dea1aca2..989277fb4c1d9bdb5cf3fecf9d98c744fccf2c33 100644
--- a/third_party/WebKit/Source/core/html/HTMLCanvasElement.h
+++ b/third_party/WebKit/Source/core/html/HTMLCanvasElement.h
@@ -36,6 +36,7 @@
 #include "core/dom/DocumentVisibilityObserver.h"
 #include "core/fileapi/FileCallback.h"
 #include "core/html/HTMLElement.h"
+#include "core/html/canvas/CanvasDrawListener.h"
 #include "core/html/canvas/CanvasImageSource.h"
 #include "platform/geometry/FloatRect.h"
 #include "platform/geometry/IntSize.h"
@@ -101,6 +102,10 @@ public:
     void toBlob(FileCallback*, const String& mimeType, const ScriptValue& qualityArgument, ExceptionState&);
     void toBlob(FileCallback* callback, const String& mimeType, ExceptionState& exceptionState) { return toBlob(callback, mimeType, ScriptValue(), exceptionState); }
 
+    // Used for canvas capture.
+    void addListener(CanvasDrawListener*);
+    void removeListener(CanvasDrawListener*);
+
     // Used for rendering
     void didDraw(const FloatRect&);
 
@@ -193,9 +198,13 @@ private:
 
     bool paintsIntoCanvasBuffer() const;
 
+    void notifyListenersCanvasChanged();
+
     ImageData* toImageData(SourceDrawingBuffer) const;
     String toDataURLInternal(const String& mimeType, const double& quality, SourceDrawingBuffer) const;
 
+    WillBeHeapHashSet<RawPtrWillBeMember<CanvasDrawListener>> m_listeners;

[peria, 2015/11/24 05:50:22]

Can this type be
PersistentHeapHashSetWillBeHeapHashSet<WeakMember<CanvasDrawListener>>
?

[emircan, 2015/11/24 22:16:51]

Done.

+
     IntSize m_size;
 
     OwnPtrWillBeMember<CanvasRenderingContext> m_context;