Let every "accelerated IO surface swapped" message have an identifier of the surface.

chrome/browser/renderer_host/accelerated_surface_container_mac.cc

 // 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.
 
 #include "chrome/browser/renderer_host/accelerated_surface_container_mac.h"
 
 #include "app/surface/io_surface_support_mac.h"
 #include "base/logging.h"
 #include "chrome/browser/renderer_host/accelerated_surface_container_manager_mac.h"
 #include "webkit/glue/plugins/webplugin.h"
 
 AcceleratedSurfaceContainerMac::AcceleratedSurfaceContainerMac(
     AcceleratedSurfaceContainerManagerMac* manager,
     bool opaque)
     : manager_(manager),
       opaque_(opaque),
+      surface_id_(0),
       width_(0),
       height_(0),
       texture_(0),
       texture_needs_upload_(true),
       texture_pending_deletion_(0),
       visible_(false),
       was_painted_to_(false) {
 }
 
 AcceleratedSurfaceContainerMac::~AcceleratedSurfaceContainerMac() {
 }
 
 void AcceleratedSurfaceContainerMac::SetSizeAndIOSurface(
     int32 width,
     int32 height,
     uint64 io_surface_identifier) {
   surface_.reset();
+  surface_id_ = 0;
   IOSurfaceSupport* io_surface_support = IOSurfaceSupport::Initialize();
   if (io_surface_support) {
     surface_.reset(io_surface_support->IOSurfaceLookup(
         static_cast<uint32>(io_surface_identifier)));
+    if (surface_.get())
+      surface_id_ = io_surface_identifier;
     EnqueueTextureForDeletion();
     width_ = width;
     height_ = height;
   }
 }
 
 void AcceleratedSurfaceContainerMac::SetSizeAndTransportDIB(
     int32 width,
     int32 height,
     TransportDIB::Handle transport_dib) {
@@ skipping 137 matching lines @@
       glVertex3f(0, clipHeight, 0);
 
       glTexCoord2f(clipX + clipWidth, height_ - clipY - clipHeight);
       glVertex3f(clipWidth, clipHeight, 0);
 
     glEnd();
     glDisable(target);
   }
 }
 
+void AcceleratedSurfaceContainerMac::set_was_painted_to(uint64 surface_id) {
+  if (surface_id) {
+    // Check that only the most current IOSurface allocated for this container
+    // is painted to.
+    DCHECK(surface_);
+    DCHECK_EQ(surface_id, surface_id_);
+  }
+  was_painted_to_ = true;
+}
+
 void AcceleratedSurfaceContainerMac::EnqueueTextureForDeletion() {
   if (texture_) {
     DCHECK(texture_pending_deletion_ == 0);
     texture_pending_deletion_ = texture_;
     texture_ = 0;
   }
 }