cc: Add CopyResource function to ResourceProvider API.

cc/resources/resource_provider.h

 // Copyright 2012 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 CC_RESOURCES_RESOURCE_PROVIDER_H_
 #define CC_RESOURCES_RESOURCE_PROVIDER_H_
 
 #include <deque>
 #include <set>
 #include <string>
@@ skipping 306 matching lines @@
    private:
     DISALLOW_COPY_AND_ASSIGN(Fence);
   };
 
   // Returns a canvas for direct rasterization.
   // Call Unmap before the resource can be read or used for compositing.
   // It is used for direct gpu rasterization.
   SkCanvas* MapDirectRasterBuffer(ResourceId id);
   void UnmapDirectRasterBuffer(ResourceId id);
 
-  // Returns a canvas backed by an image buffer.
+  // Returns a canvas backed by an image buffer. UnmapImageRasterBuffer
+  // returns true if canvas was written to while mapped.
   // Rasterizing to the canvas writes the content into the image buffer,
   // which is internally bound to the underlying resource when read.
   // Call Unmap before the resource can be read or used for compositing.
   // It is used by ImageRasterWorkerPool.
   SkCanvas* MapImageRasterBuffer(ResourceId id);
-  void UnmapImageRasterBuffer(ResourceId id);
+  bool UnmapImageRasterBuffer(ResourceId id);
 
   // Returns a canvas backed by pixel buffer. UnmapPixelRasterBuffer
   // returns true if canvas was written to while mapped.
   // The pixel buffer needs to be uploaded to the underlying resource
   // using BeginSetPixels before the resouce can be used for compositing.
   // It is used by PixelRasterWorkerPool.
   void AcquirePixelRasterBuffer(ResourceId id);
   void ReleasePixelRasterBuffer(ResourceId id);
   SkCanvas* MapPixelRasterBuffer(ResourceId id);
   bool UnmapPixelRasterBuffer(ResourceId id);
@@ skipping 19 matching lines @@
     current_read_lock_fence_ = fence;
   }
   Fence* GetReadLockFence() { return current_read_lock_fence_.get(); }
 
   // Enable read lock fences for a specific resource.
   void EnableReadLockFences(ResourceProvider::ResourceId id, bool enable);
 
   // Indicates if we can currently lock this resource for write.
   bool CanLockForWrite(ResourceId id);
 
+  // Copy pixels from source to destination.
+  void CopyResource(ResourceId source_id, ResourceId dest_id);
+
   static GLint GetActiveTextureUnit(gpu::gles2::GLES2Interface* gl);
 
  private:
   class DirectRasterBuffer;
   class ImageRasterBuffer;
   class PixelRasterBuffer;
 
   struct Resource {
     enum Origin { Internal, External, Delegated };
 
@@ skipping 19 matching lines @@
              Origin origin,
              GLenum filter,
              GLint wrap_mode);
 
     int child_id;
     unsigned gl_id;
     // Pixel buffer used for set pixels without unnecessary copying.
     unsigned gl_pixel_buffer_id;
     // Query used to determine when asynchronous set pixels complete.
     unsigned gl_upload_query_id;
+    // Query used to determine when read lock fence has passed.
+    unsigned gl_read_lock_query_id;
     TextureMailbox mailbox;
     ReleaseCallback release_callback;
     uint8_t* pixels;
     int lock_for_read_count;
     int imported_count;
     int exported_count;
     bool dirty_image : 1;
     bool locked_for_write : 1;
     bool lost : 1;
     bool marked_for_deletion : 1;
@@ skipping 269 matching lines @@
   return format_gl_data_format[format];
 }
 
 inline GLenum GLInternalFormat(ResourceFormat format) {
   return GLDataFormat(format);
 }
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_RESOURCE_PROVIDER_H_