Improve GCM enum switch type safety

components/gcm_driver/instance_id/instance_id_impl.cc

 // 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.
 
 #include "components/gcm_driver/instance_id/instance_id_impl.h"
 
 #include <stdint.h>
 
 #include <algorithm>
 #include <memory>
@@ skipping 11 matching lines @@
 
 namespace {
 
 InstanceID::Result GCMClientResultToInstanceIDResult(
     gcm::GCMClient::Result result) {
   switch (result) {
     case gcm::GCMClient::SUCCESS:
       return InstanceID::SUCCESS;
     case gcm::GCMClient::INVALID_PARAMETER:
       return InstanceID::INVALID_PARAMETER;
+    case gcm::GCMClient::GCM_DISABLED:
+      return InstanceID::DISABLED;
     case gcm::GCMClient::ASYNC_OPERATION_PENDING:
       return InstanceID::ASYNC_OPERATION_PENDING;
-    case gcm::GCMClient::GCM_DISABLED:
-      return InstanceID::DISABLED;
     case gcm::GCMClient::NETWORK_ERROR:
       return InstanceID::NETWORK_ERROR;
     case gcm::GCMClient::SERVER_ERROR:
       return InstanceID::SERVER_ERROR;
     case gcm::GCMClient::UNKNOWN_ERROR:
       return InstanceID::UNKNOWN_ERROR;
-    default:
-      NOTREACHED() << "Unexpected value of result cannot be converted: "
-                   << result;
+    case gcm::GCMClient::TTL_EXCEEDED:
+      NOTREACHED();
+      break;
   }
   return InstanceID::UNKNOWN_ERROR;
 }
 
 }  // namespace
 
 // static
 std::unique_ptr<InstanceID> InstanceID::CreateInternal(
     const std::string& app_id,
     gcm::GCMDriver* gcm_driver) {
@@ skipping 214 matching lines @@
 }
 
 gcm::InstanceIDHandler* InstanceIDImpl::Handler() {
   gcm::InstanceIDHandler* handler =
       gcm_driver()->GetInstanceIDHandlerInternal();
   DCHECK(handler);
   return handler;
 }
 
 }  // namespace instance_id