Mac: Fix renderer idle cpu usage regression.

chrome/browser/notifications/balloon_host.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/notifications/balloon_host.h"
 
 #include "chrome/browser/browser_list.h"
 #include "chrome/browser/in_process_webkit/webkit_context.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 #include "chrome/browser/notifications/balloon.h"
 #include "chrome/browser/profile.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
 #include "chrome/browser/renderer_host/site_instance.h"
 #include "chrome/browser/renderer_preferences_util.h"
 #include "chrome/common/bindings_policy.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/notification_type.h"
+#include "chrome/common/render_messages.h"
 #include "chrome/common/renderer_preferences.h"
 #include "chrome/common/url_constants.h"
 
 BalloonHost::BalloonHost(Balloon* balloon)
     : render_view_host_(NULL),
       balloon_(balloon),
       initialized_(false),
       should_notify_on_disconnect_(false) {
   DCHECK(balloon_);
 
@@ skipping 22 matching lines @@
   WebPreferences prefs;
   prefs.allow_scripts_to_close_windows = true;
   return prefs;
 }
 
 void BalloonHost::Close(RenderViewHost* render_view_host) {
   balloon_->CloseByScript();
 }
 
 void BalloonHost::RenderViewCreated(RenderViewHost* render_view_host) {
-  render_view_host->EnablePreferredSizeChangedMode();
+  render_view_host->EnablePreferredSizeChangedMode(
+      kPreferredSizeWidth | kPreferredSizeHeightThisIsSlow);
 }
 
 void BalloonHost::RenderViewReady(RenderViewHost* render_view_host) {
   should_notify_on_disconnect_ = true;
   NotificationService::current()->Notify(
       NotificationType::NOTIFY_BALLOON_CONNECTED,
       Source<BalloonHost>(this), NotificationService::NoDetails());
 }
 
 void BalloonHost::RenderViewGone(RenderViewHost* render_view_host) {
@@ skipping 82 matching lines @@
 
 void BalloonHost::NotifyDisconnect() {
   if (!should_notify_on_disconnect_)
     return;
 
   should_notify_on_disconnect_ = false;
   NotificationService::current()->Notify(
       NotificationType::NOTIFY_BALLOON_DISCONNECTED,
       Source<BalloonHost>(this), NotificationService::NoDetails());
 }