Avoid GPU readback in tex(Sub)Image2D(ImageBitmap)

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

Index: third_party/WebKit/Source/platform/graphics/StaticBitmapImage.h
diff --git a/third_party/WebKit/Source/platform/graphics/StaticBitmapImage.h b/third_party/WebKit/Source/platform/graphics/StaticBitmapImage.h
index 001e3b01b93b3145e6792ca8fc9bc93c112ef843..9113bc4ffc5a91a528d64cf54e6d2002853b4158 100644
--- a/third_party/WebKit/Source/platform/graphics/StaticBitmapImage.h
+++ b/third_party/WebKit/Source/platform/graphics/StaticBitmapImage.h
@@ -7,6 +7,7 @@
 
 #include "platform/graphics/Image.h"
 #include "public/platform/WebExternalTextureMailbox.h"
+#include "third_party/khronos/GLES2/gl2.h"
 
 namespace blink {
 
@@ -23,18 +24,29 @@ public:
     virtual IntSize size() const;
     void draw(SkCanvas*, const SkPaint&, const FloatRect& dstRect, const FloatRect& srcRect, RespectImageOrientationEnum, ImageClampingMode) override;
 
-    PassRefPtr<SkImage> imageForCurrentFrame() override;
+    PassRefPtr<SkImage> imageForCurrentFrame(WebGraphicsContext3DProvider* = nullptr) override;
 
     bool originClean() const { return m_isOriginClean; }
     void setOriginClean(bool flag) { m_isOriginClean = flag; }
     bool isPremultiplied() const { return m_isPremultiplied; }
     void setPremultiplied(bool flag) { m_isPremultiplied = flag; }
+    void copyTexture(WebGraphicsContext3DProvider*, GLuint, GLenum, GLenum);
+    bool hasContext3DProvider() const { return !!m_provider; }

[Justin Novosad, 2016/06/07 15:11:07]

!! is not necessary You should only use that when coercion to bool is necessary.
 Pointers convert implicitly to bool just fine.

[xidachen, 2016/06/07 17:49:54]

I am not sure how windows bots will react to this, so removing the !! and will
have win bots to try.

+    bool hasSkImage() const { return !!m_image; }

[Justin Novosad, 2016/06/07 15:11:07]

same here

+
 protected:
     StaticBitmapImage(PassRefPtr<SkImage>);
     StaticBitmapImage(WebExternalTextureMailbox&);
 
+private:
+    void consumeTextureMailbox(WebGraphicsContext3DProvider*);
+    bool prepareMailboxForSkImage(WebGraphicsContext3DProvider*);
+
     RefPtr<SkImage> m_image;
     WebExternalTextureMailbox m_mailbox;
+    OwnPtr<WebGraphicsContext3DProvider> m_provider;
+    // Cached textureId from CreateAndConsumeTextureCHROMIUM
+    GLuint m_textureId = 0;
     bool m_isOriginClean = true;
     // The premultiply info is stored here because the SkImage API
     // doesn't expose this info.