[GCM] Add more UMA to GCM

google_apis/gcm/engine/unregistration_request.h

Index: google_apis/gcm/engine/unregistration_request.h
diff --git a/google_apis/gcm/engine/unregistration_request.h b/google_apis/gcm/engine/unregistration_request.h
index b25e28c137dc8bd9fd90c3d3de6a3e630751a518..aec3331d18a0953a5d6287c299e3c6573f30bd95 100644
--- a/google_apis/gcm/engine/unregistration_request.h
+++ b/google_apis/gcm/engine/unregistration_request.h
@@ -10,6 +10,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "base/time/time.h"
 #include "google_apis/gcm/base/gcm_export.h"
 #include "net/base/backoff_entry.h"
 #include "net/url_request/url_fetcher_delegate.h"
@@ -99,6 +100,7 @@ class GCM_EXPORT UnregistrationRequest : public net::URLFetcherDelegate {
   net::BackoffEntry backoff_entry_;
   scoped_refptr<net::URLRequestContextGetter> request_context_getter_;
   scoped_ptr<net::URLFetcher> url_fetcher_;
+  base::TimeTicks request_start_time_;
 
   // Recorder that records GCM activities for debugging purpose. Not owned.
   GCMStatsRecorder* recorder_;