Add rendering context and rendering 2D context to OffscreenCanvas

third_party/WebKit/Source/modules/offscreencanvas/OffscreenCanvasRenderingContextFactory.h

-// Copyright 2015 The Chromium Authors. All rights reserved.
+// Copyright (c) 2016 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 ImagePixelLocker_h
-#define ImagePixelLocker_h
+#ifndef OffscreenCanvasRenderingContextFactory_h
+#define OffscreenCanvasRenderingContextFactory_h
 
-#include "platform/heap/Heap.h"
-#include "third_party/skia/include/core/SkImageInfo.h"
-#include "third_party/skia/include/core/SkPixmap.h"
 #include "wtf/Allocator.h"
-#include "wtf/Noncopyable.h"
 #include "wtf/PassRefPtr.h"
-#include "wtf/RefPtr.h"
-
-class SkImage;
 
 namespace blink {
 
-class ImagePixelLocker final {
-    DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
-    WTF_MAKE_NONCOPYABLE(ImagePixelLocker);
+class CanvasContextCreationAttributes;
+class OffscreenCanvas;
+class OffscreenCanvasRenderingContext;
+
+class OffscreenCanvasRenderingContextFactory {
+    USING_FAST_MALLOC(OffscreenCanvasRenderingContextFactory);
+    WTF_MAKE_NONCOPYABLE(OffscreenCanvasRenderingContextFactory);
 public:
-    ImagePixelLocker(PassRefPtr<const SkImage>, SkAlphaType, SkColorType);
+    OffscreenCanvasRenderingContextFactory() = default;
+    virtual ~OffscreenCanvasRenderingContextFactory() { }
 
-    const void* pixels() const { return m_pixels; }
-
-private:
-    const RefPtr<const SkImage> m_image;
-    const void* m_pixels;
-    SkAutoPixmapStorage m_pixelStorage;
+    virtual OffscreenCanvasRenderingContext* create(OffscreenCanvas*, const CanvasContextCreationAttributes&) = 0;
+    virtual OffscreenCanvasRenderingContext::ContextType contextType() const = 0;
+    virtual void onError(OffscreenCanvas*, const String& error) = 0;
 };
 
 } // namespace blink
 
-#endif
+#endif // OffscreenCanvasRenderingContextFactory_h