Push API: Add and cleanup UMA logging for unregister/get/delivery.

chrome/browser/services/gcm/push_messaging_browsertest.cc

 // Copyright 2014 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 <map>
 #include <string>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 717 matching lines @@
   if (!IsPushSupported())
     return;
 
   std::string script_result;
 
   TryToRegisterSuccessfully("1-0" /* expected_push_registration_id */);
 
   gcm_service()->AddExpectedUnregisterResponse(GCMClient::NETWORK_ERROR);
 
   ASSERT_TRUE(RunScript("unregister()", &script_result));
-  EXPECT_EQ("unregister error: "
-            "NetworkError: Failed to connect to the push server.",
+  EXPECT_EQ("unregister error: NetworkError: "
+            "Unregistration failed - could not connect to push server",
             script_result);
 }
 
-IN_PROC_BROWSER_TEST_F(PushMessagingBrowserTest, UnregisterUnknownError) {
+IN_PROC_BROWSER_TEST_F(PushMessagingBrowserTest, UnregisterAbortError) {
   if (!IsPushSupported())
     return;
 
   std::string script_result;
 
   TryToRegisterSuccessfully("1-0" /* expected_push_registration_id */);
 
   gcm_service()->AddExpectedUnregisterResponse(GCMClient::UNKNOWN_ERROR);
 
   ASSERT_TRUE(RunScript("unregister()", &script_result));
   EXPECT_EQ("unregister error: "
-            "UnknownError: Unexpected error while trying to unregister from the"
-            " push server.", script_result);
+            "AbortError: Unregistration failed - push service error",
+            script_result);
 }
 
 #if defined(OS_ANDROID)
 IN_PROC_BROWSER_TEST_F(PushMessagingBrowserTest, PushUnavailableOnAndroidICS) {
   // This test should only run on Android ICS to confirm that the Push API
   // is not available on that version of Android.
   if (IsPushSupported())
     return;
 
   std::string script_result;
@@ skipping 235 matching lines @@
   // left without permission to use Push.
 
   ASSERT_TRUE(RunScript("hasPermission()", &script_result));
   EXPECT_EQ("permission status - granted", script_result);
 
   ASSERT_TRUE(RunScript("hasRegistration()", &script_result));
   EXPECT_EQ("true - registered", script_result);
 }
 
 }  // namespace gcm