UMA stats for MTP file system in Chrome OS Files.app.

chrome/browser/chromeos/extensions/file_manager/private_api_util.cc

 // Copyright 2013 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 "chrome/browser/chromeos/extensions/file_manager/private_api_util.h"
 
 #include <string>
 
 #include "base/files/file_path.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 150 matching lines @@
     case VOLUME_TYPE_PROVIDED:
       volume_metadata->volume_type = file_browser_private::VOLUME_TYPE_PROVIDED;
       break;
     case VOLUME_TYPE_MTP:
       volume_metadata->volume_type = file_browser_private::VOLUME_TYPE_MTP;
       break;
     case VOLUME_TYPE_TESTING:
       volume_metadata->volume_type =
           file_browser_private::VOLUME_TYPE_TESTING;
       break;
+    case NUM_VOLUME_TYPE:
+      NOTREACHED();
+      break;
   }
 
   // Fill device_type iff the volume is removable partition.
   if (volume_info.type == VOLUME_TYPE_REMOVABLE_DISK_PARTITION) {
     switch (volume_info.device_type) {
       case chromeos::DEVICE_TYPE_UNKNOWN:
         volume_metadata->device_type =
             file_browser_private::DEVICE_TYPE_UNKNOWN;
         break;
       case chromeos::DEVICE_TYPE_USB:
@@ skipping 98 matching lines @@
 
 drive::EventLogger* GetLogger(Profile* profile) {
   drive::DriveIntegrationService* service =
       drive::DriveIntegrationServiceFactory::FindForProfileRegardlessOfStates(
           profile);
   return service ? service->event_logger() : NULL;
 }
 
 }  // namespace util
 }  // namespace file_manager