Adding histograms showing fraction of page load times

chrome/browser/ui/tab_contents/tab_contents.h

Index: chrome/browser/ui/tab_contents/tab_contents.h
===================================================================
--- chrome/browser/ui/tab_contents/tab_contents.h	(revision 148459)
+++ chrome/browser/ui/tab_contents/tab_contents.h	(working copy)
@@ -64,6 +64,10 @@
 }
 }
 
+namespace chrome_browser_net {
+class CacheStatsTabHelper;
+}
+
 namespace extensions {
 class TabHelper;
 class WebNavigationTabObserver;
@@ -266,6 +270,7 @@
   scoped_ptr<AutomationTabHelper> automation_tab_helper_;
   scoped_ptr<BlockedContentTabHelper> blocked_content_tab_helper_;
   scoped_ptr<BookmarkTabHelper> bookmark_tab_helper_;
+  scoped_ptr<chrome_browser_net::CacheStatsTabHelper> cache_stats_tab_helper_;
 #if defined(ENABLE_CAPTIVE_PORTAL_DETECTION)
   scoped_ptr<captive_portal::CaptivePortalTabHelper> captive_portal_tab_helper_;
 #endif