Support copying a partial rectangle region from the compositing surface on Aura and GTK.

content/browser/renderer_host/render_widget_host_view_mac.mm

Index: content/browser/renderer_host/render_widget_host_view_mac.mm
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.mm b/content/browser/renderer_host/render_widget_host_view_mac.mm
index 2a399b7256de198c95f3076a3f65b88c84f4c5ee..7f882134183824ab2db16f321210f40329f1f5d6 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac.mm
@@ -816,8 +816,11 @@ BackingStore* RenderWidgetHostViewMac::AllocBackingStore(
   return new BackingStoreMac(render_widget_host_, size, scale);
 }
 
+// TODO(mazda): Support copying a partial rectangle from the compositing surface
+// with |src_subrect| (http://crbug.com/118571).
 void RenderWidgetHostViewMac::CopyFromCompositingSurface(
-    const gfx::Size& size,
+    const gfx::Rect& /* src_subrect */,
+    const gfx::Size& dst_size,
     const base::Callback<void(bool)>& callback,
     skia::PlatformCanvas* output) {

[piman, 2012/07/26 00:04:51]

For mac and windows, where subrects are not supported, we should have a
NOTIMPLEMENTED() if !src_subrect.IsEmpty().

[mazda, 2012/07/26 02:20:04]

Done.

   base::ScopedClosureRunner scoped_callback_runner(base::Bind(callback, false));
@@ -825,11 +828,11 @@ void RenderWidgetHostViewMac::CopyFromCompositingSurface(
       !compositing_iosurface_->HasIOSurface())
     return;
 
-  if (!output->initialize(size.width(), size.height(), true))
+  if (!output->initialize(dst_size.width(), dst_size.height(), true))
     return;
 
   const bool result = compositing_iosurface_->CopyTo(
-      size, output->getTopDevice()->accessBitmap(true).getPixels());
+      dst_size, output->getTopDevice()->accessBitmap(true).getPixels());
   scoped_callback_runner.Release();
   callback.Run(result);
 }