Refactor AcceleratedStaticBitmapImage

third_party/WebKit/Source/platform/graphics/SkiaTextureHolder.h

+// Copyright 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 SkiaTextureHolder_h
+#define SkiaTextureHolder_h
+
+#include "platform/PlatformExport.h"
+#include "platform/graphics/TextureHolder.h"
+
+namespace blink {
+
+class PLATFORM_EXPORT SkiaTextureHolder final : public TextureHolder {
+ public:
+  ~SkiaTextureHolder() override;
+
+  bool isSkiaTextureHolder() final { return true; }
+  bool isMailboxTextureHolder() final { return false; }
+  unsigned sharedContextId() final;
+  WebThread* imageThread() final { return m_imageThread; }
+  IntSize size() const final {
+    return IntSize(m_image->width(), m_image->height());
+  }
+
+  sk_sp<SkImage> skImage() final { return m_image; }
+  void setSharedContextId(unsigned contextId) final {
+    m_sharedContextId = contextId;
+  }
+  void setImageThread(WebThread* thread) { m_imageThread = thread; }

[Justin Novosad, 2016/11/03 17:37:47]

this is probably not safe. I though you were going to change this for a
unique_ptr<WebTaskRunner> that holds a clone.

[xidachen, 2016/11/03 20:03:10]

Done.

+
+  // When creating a AcceleratedStaticBitmap from a texture-backed SkImage, this
+  // function will be called to create a TextureHolder object.
+  SkiaTextureHolder(sk_sp<SkImage>);
+  // This function consumes the mailbox in the input parameter and turn it into
+  // a texture-backed SkImage.
+  SkiaTextureHolder(std::unique_ptr<TextureHolder>);
+
+ private:
+  void releaseImageThreadSafe();
+
+  // The m_image should always be texture-backed
+  sk_sp<SkImage> m_image;
+  // Id of the shared context where m_image was created
+  unsigned m_sharedContextId = 0;
+  // Thread that |m_image| belongs to. Set to null when |m_image| belongs to the
+  // same thread as the AcceleratedStaticBitmapImage.  Should only be non-null
+  // after a transfer.
+  WebThread* m_imageThread = nullptr;
+};
+
+}  // namespace blink
+
+#endif  // SkiaTextureHolder_h