Revert of Remove code used by --disable-delegated-renderer on Mac

content/browser/renderer_host/compositing_iosurface_mac.h

Index: content/browser/renderer_host/compositing_iosurface_mac.h
diff --git a/content/browser/renderer_host/compositing_iosurface_mac.h b/content/browser/renderer_host/compositing_iosurface_mac.h
index 14a799360673df174a07d89787269afc5761f9e7..08c3c74c286fa8cfe0700d1e6d0b0cd0e10335e9 100644
--- a/content/browser/renderer_host/compositing_iosurface_mac.h
+++ b/content/browser/renderer_host/compositing_iosurface_mac.h
@@ -169,9 +169,48 @@
     SurfaceVertex verts_[4];
   };
 
+  // Keeps track of states and buffers for readback of IOSurface.
+  //
+  // TODO(miu): Major code refactoring is badly needed!  To be done in a
+  // soon-upcoming change.  For now, we blatantly violate the style guide with
+  // respect to struct vs. class usage:
+  struct CopyContext {
+    explicit CopyContext(const scoped_refptr<CompositingIOSurfaceContext>& ctx);
+    ~CopyContext();
+
+    // Delete any references to owned OpenGL objects.  This must be called
+    // within the OpenGL context just before destruction.
+    void ReleaseCachedGLObjects();
+
+    // The following two methods assume |num_outputs| has been set, and are
+    // being called within the OpenGL context.
+    void PrepareReadbackFramebuffers();
+    void PrepareForAsynchronousReadback();
+
+    const scoped_ptr<CompositingIOSurfaceTransformer> transformer;
+    GLenum output_readback_format;
+    int num_outputs;
+    GLuint output_textures[3];  // Not owned.
+    // Note: For YUV, the |output_texture_sizes| widths are in terms of 4-byte
+    // quads, not pixels.
+    gfx::Size output_texture_sizes[3];
+    GLuint frame_buffers[3];
+    GLuint pixel_buffers[3];
+    GLuint fence;  // When non-zero, doing an asynchronous copy.
+    int cycles_elapsed;
+    base::Callback<bool(const void*, int)> map_buffer_callback;
+    base::Callback<void(bool)> done_callback;
+  };
+
   CompositingIOSurfaceMac(
       const scoped_refptr<CompositingIOSurfaceContext>& context);
   ~CompositingIOSurfaceMac();
+
+  // If this IOSurface has moved to a different window, use that window's
+  // GL context (if multiple visible windows are using the same GL context
+  // then call to setView call can stall and prevent reaching 60fps).
+  void SwitchToContextOnNewWindow(NSView* view,
+                                  int window_number);
 
   // Returns true if IOSurface is ready to render. False otherwise.
   bool MapIOSurfaceToTextureWithContextCurrent(
@@ -184,9 +223,53 @@
 
   void DrawQuad(const SurfaceQuad& quad);
 
+  // Copy current frame to |target| video frame. This method must be called
+  // within a CGL context. Returns a callback that should be called outside
+  // of the CGL context.
+  // If |called_within_draw| is true this method is called within a drawing
+  // operations. This allow certain optimizations.
+  base::Closure CopyToVideoFrameWithinContext(
+      const gfx::Rect& src_subrect,
+      bool called_within_draw,
+      const scoped_refptr<media::VideoFrame>& target,
+      const base::Callback<void(bool)>& callback);
+
+  // Common GPU-readback copy path.  Only one of |bitmap_output| or
+  // |video_frame_output| may be specified: Either ARGB is written to
+  // |bitmap_output| or letter-boxed YV12 is written to |video_frame_output|.
+  base::Closure CopyToSelectedOutputWithinContext(
+      const gfx::Rect& src_pixel_subrect,
+      const gfx::Rect& dst_pixel_rect,
+      bool called_within_draw,
+      const SkBitmap* bitmap_output,
+      const scoped_refptr<media::VideoFrame>& video_frame_output,
+      const base::Callback<void(bool)>& done_callback);
+
+  // TODO(hclam): These two methods should be static.
+  void AsynchronousReadbackForCopy(
+      const gfx::Rect& dst_pixel_rect,
+      bool called_within_draw,
+      CopyContext* copy_context,
+      const SkBitmap* bitmap_output,
+      const scoped_refptr<media::VideoFrame>& video_frame_output);
+  bool SynchronousReadbackForCopy(
+      const gfx::Rect& dst_pixel_rect,
+      CopyContext* copy_context,
+      const SkBitmap* bitmap_output,
+      const scoped_refptr<media::VideoFrame>& video_frame_output);
+
+  void CheckIfAllCopiesAreFinishedWithinContext(
+      bool block_until_finished,
+      std::vector<base::Closure>* done_callbacks);
+
+  void FailAllCopies();
+  void DestroyAllCopyContextsWithinContext();
+
   // Check for GL errors and store the result in error_. Only return new
   // errors
   GLenum GetAndSaveGLError();
+
+  gfx::Rect IntersectWithIOSurface(const gfx::Rect& rect) const;
 
   // Offscreen context used for all operations other than drawing to the
   // screen. This is in the same share group as the contexts used for
@@ -208,6 +291,16 @@
   // need to do is ensure it is re-bound before attempting to draw
   // with it.
   GLuint texture_;
+
+  // A pool of CopyContexts with OpenGL objects ready for re-use.  Prefer to
+  // pull one from the pool before creating a new CopyContext.
+  std::vector<CopyContext*> copy_context_pool_;
+
+  // CopyContexts being used for in-flight copy operations.
+  std::deque<CopyContext*> copy_requests_;
+
+  // Timer for finishing a copy operation.
+  base::Timer finish_copy_timer_;
 
   // Error saved by GetAndSaveGLError
   GLint gl_error_;