Cache the current WebPreferences on RenderViewHostImpl (try #2).

content/browser/web_contents/web_contents_impl.cc

 // Copyright (c) 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.
 
 #include "content/browser/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 3805 matching lines @@
 bool WebContentsImpl::AddMessageToConsole(int32 level,
                                           const base::string16& message,
                                           int32 line_no,
                                           const base::string16& source_id) {
   if (!delegate_)
     return false;
   return delegate_->AddMessageToConsole(this, level, message, line_no,
                                         source_id);
 }
 
-WebPreferences WebContentsImpl::GetWebkitPrefs() {
+WebPreferences WebContentsImpl::ComputeWebkitPrefs() {
   // We want to base the page config off of the actual URL, rather than the
   // virtual URL.
   // TODO(nasko): Investigate how to remove the GetActiveEntry usage here,
   // as it is deprecated and can be out of sync with GetRenderViewHost().
   GURL url = controller_.GetActiveEntry()
       ? controller_.GetActiveEntry()->GetURL() : GURL::EmptyGURL();
 
-  return GetRenderManager()->current_host()->GetWebkitPrefs(url);
+  return GetRenderManager()->current_host()->ComputeWebkitPrefs(url);
 }
 
 int WebContentsImpl::CreateSwappedOutRenderView(
     SiteInstance* instance) {
   return GetRenderManager()->CreateRenderFrame(
       instance, MSG_ROUTING_NONE, true, true, true);
 }
 
 void WebContentsImpl::OnUserGesture() {
   // Notify observers.
@@ skipping 398 matching lines @@
   if (new_size != old_size)
     delegate_->UpdatePreferredSize(this, new_size);
 }
 
 void WebContentsImpl::ResumeResponseDeferredAtStart() {
   FrameTreeNode* node = frame_tree_.root();
   node->render_manager()->ResumeResponseDeferredAtStart();
 }
 
 }  // namespace content