Reintegrate 552 r66225-r66645....

webkit/glue/plugins/webplugin_delegate_impl_mac.mm

 // Copyright (c) 2010 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.
 
 #import <Cocoa/Cocoa.h>
 #import <QuartzCore/QuartzCore.h>
 
 #include "webkit/glue/plugins/webplugin_delegate_impl.h"
 
 #include <string>
@@ skipping 963 matching lines @@
 }
 
 #pragma mark -
 #pragma mark Core Animation Support
 
 void WebPluginDelegateImpl::DrawLayerInSurface() {
   // If we haven't plumbed up the surface yet, don't try to draw.
   if (!windowed_handle())
     return;
 
-  surface_->StartDrawing();
-
   [renderer_ beginFrameAtTime:CACurrentMediaTime() timeStamp:NULL];
   if (CGRectIsEmpty([renderer_ updateBounds])) {
     // If nothing has changed, we are done.
     [renderer_ endFrame];
     return;
   }
+
+  surface_->StartDrawing();
+
   CGRect layerRect = [layer_ bounds];
   [renderer_ addUpdateRect:layerRect];
   [renderer_ render];
   [renderer_ endFrame];
 
   surface_->EndDrawing();
 }
 
 // Update the size of the surface to match the current size of the plug-in.
 void WebPluginDelegateImpl::UpdateAcceleratedSurface() {
@@ skipping 127 matching lines @@
     return;
   }
 
   qd_manager_->SetFastPathEnabled(enabled);
   qd_port_.port = qd_manager_->port();
   WindowlessSetWindow();
   // Send a paint event so that the new buffer gets updated immediately.
   WindowlessPaint(buffer_context_, clip_rect_);
 }
 #endif  // !NP_NO_QUICKDRAW