Filter out redundant jumplist updates.

chrome/browser/jumplist_win.h

Index: chrome/browser/jumplist_win.h
diff --git a/chrome/browser/jumplist_win.h b/chrome/browser/jumplist_win.h
index cd46088eb9a6d3103224adf3b3d77111fbf6f712..86f6791bd547840d9e15fbc887f8538ddaad4957 100644
--- a/chrome/browser/jumplist_win.h
+++ b/chrome/browser/jumplist_win.h
@@ -14,6 +14,7 @@
 #include "base/memory/weak_ptr.h"
 #include "base/synchronization/lock.h"
 #include "base/task/cancelable_task_tracker.h"
+#include "base/time/time.h"
 #include "chrome/browser/jumplist_updater_win.h"
 #include "chrome/browser/prefs/incognito_mode_prefs.h"
 #include "chrome/browser/sessions/tab_restore_service.h"
@@ -162,6 +163,11 @@ class JumpList : public TabRestoreServiceObserver,
   // protected by the list_lock_.
   ShellLinkItemList recently_closed_pages_;
 
+  // Track the last time a jumplist update was requested, and the last time
+  // such an update was requested. These are protected by list_lock_.

[gab, 2015/03/31 13:10:14]

s/requested/started

[gab, 2015/03/31 13:10:14]

s/list_lock_/|list_lock_|

+  base::TimeTicks lastUpdateRequested_;

[jochen (gone - plz use gerrit), 2015/03/31 10:28:52]

last_update_requested_

+  base::TimeTicks lastUpdateStarted_;
+
   // A list of URLs we need to retrieve their favicons,
   // protected by the list_lock_.
   typedef std::pair<std::string, scoped_refptr<ShellLinkItem> > URLPair;