Add various UMA histograms for measuring GCM crypto performance

components/gcm_driver/gcm_stats_recorder_android.h

 // Copyright 2015 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.
 
 #ifndef COMPONENTS_GCM_DRIVER_GCM_STATS_RECORDER_ANDROID_H_
 #define COMPONENTS_GCM_DRIVER_GCM_STATS_RECORDER_ANDROID_H_
 
 #include <deque>
 #include <string>
 
@@ skipping 41 matching lines @@
   void RecordUnregistrationSent(const std::string& app_id);
 
   // Records that the unregistration sent for |app_id| has received a response.
   // |success| indicates whether the unregistration was successful.
   void RecordUnregistrationResponse(const std::string& app_id, bool success);
 
   // Records that a data message has been received for |app_id|.
   void RecordDataMessageReceived(const std::string& app_id,
                                  int message_byte_size);
 
-  // Records a message decryption failure caused by |reason| for |app_id|.
+  // Records a message decryption failure caused by |result| for |app_id|.
   void RecordDecryptionFailure(const std::string& app_id,
-                               GCMEncryptionProvider::DecryptionFailure reason);
+                               GCMEncryptionProvider::DecryptionResult result);
 
   bool is_recording() const { return is_recording_; }
   void set_is_recording(bool recording) { is_recording_ = recording; }
 
  private:
   void RecordRegistration(const std::string& app_id,
                           const std::string& event,
                           const std::string& details);
 
   // Delegate made available by the container. May be a nullptr.
@@ skipping 10 matching lines @@
 
   // Recorded message decryption failure activities.
   std::deque<DecryptionFailureActivity> decryption_failure_activities_;
 
   DISALLOW_COPY_AND_ASSIGN(GCMStatsRecorderAndroid);
 };
 
 }  // namespace gcm
 
 #endif  // COMPONENTS_GCM_DRIVER_GCM_STATS_RECORDER_ANDROID_H_