Add more UMAs for Instance ID

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 61d9bff26692356399e5ed035c1f7862e448fe76..0f54538f77b6958059a27ddcfd949e371bff8fa2 100644
--- a/google_apis/gcm/engine/unregistration_request.h
+++ b/google_apis/gcm/engine/unregistration_request.h
@@ -86,6 +86,11 @@ class GCM_EXPORT UnregistrationRequest : public net::URLFetcherDelegate {
     // Parses the HTTP response. It is called after
     // UnregistrationRequest::ParseResponse to proceed the parsing.
     virtual Status ParseResponse(const net::URLFetcher* source) = 0;
+
+    // Reports various UMAs, including status, retry count and completion time.
+    virtual void ReportUMAs(Status status,
+                            int retry_count,
+                            base::TimeDelta complete_time) = 0;
   };
 
   // Creates an instance of UnregistrationRequest. |callback| will be called