Add rendering context and rendering 2D context to OffscreenCanvas

third_party/WebKit/Source/core/html/canvas/OffscreenCanvasRenderingContextFactory.h

Index: third_party/WebKit/Source/core/html/canvas/OffscreenCanvasRenderingContextFactory.h
diff --git a/third_party/WebKit/Source/core/html/canvas/OffscreenCanvasRenderingContextFactory.h b/third_party/WebKit/Source/core/html/canvas/OffscreenCanvasRenderingContextFactory.h
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index 0000000000000000000000000000000000000000..0a6776dc8a9dc938e54ceea199a8bbc8f5fb651f
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+++ b/third_party/WebKit/Source/core/html/canvas/OffscreenCanvasRenderingContextFactory.h
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+// Copyright (c) 2015 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.
+
+#include "core/CoreExport.h"
+#include "wtf/Allocator.h"
+#include "wtf/PassRefPtr.h"
+
+namespace blink {
+
+class CanvasContextCreationAttributes;
+class OffscreenCanvas;
+class OffscreenCanvasRenderingContext;
+
+class CORE_EXPORT OffscreenCanvasRenderingContextFactory {
+    USING_FAST_MALLOC(OffscreenCanvasRenderingContextFactory);
+    WTF_MAKE_NONCOPYABLE(OffscreenCanvasRenderingContextFactory);
+public:
+    OffscreenCanvasRenderingContextFactory() = default;
+    virtual ~OffscreenCanvasRenderingContextFactory() { }
+
+    virtual PassOwnPtrWillBeRawPtr<OffscreenCanvasRenderingContext> create(OffscreenCanvas*, const CanvasContextCreationAttributes&) = 0;
+    virtual OffscreenCanvasRenderingContext::ContextType contextType() const = 0;
+    virtual void onError(OffscreenCanvas*, const String& error) = 0;
+};
+
+} // namespace blink
+