Combine boolean MediaDeviceNotifications histograms to an enumerated histogram.

chrome/browser/system_monitor/media_transfer_protocol_device_observer_chromeos.cc

 // Copyright (c) 2012 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/system_monitor/media_transfer_protocol_device_observer_chromeos.h"
 
-#include "base/metrics/histogram.h"
 #include "base/stl_util.h"
 #include "base/string_number_conversions.h"
 #include "base/string_split.h"
 #include "base/stringprintf.h"
 #include "base/system_monitor/system_monitor.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/chromeos/mtp/media_transfer_protocol_manager.h"
+#include "chrome/browser/system_monitor/media_storage_util.h"
 #include "chrome/browser/system_monitor/removable_device_constants.h"
-#include "chrome/browser/system_monitor/media_storage_util.h"
 #include "chromeos/dbus/mtp_storage_info.pb.h"
 
 namespace chromeos {
 namespace mtp {
 
 using chrome::MediaStorageUtil;
 
 namespace {
 
 // Device root path constant.
@@ skipping 118 matching lines @@
 
   // New storage is attached.
   if (is_attached) {
     std::string device_id;
     string16 device_name;
     std::string location;
     get_storage_info_func_(storage_name, &device_id, &device_name, &location);
 
     // Keep track of device id and device name to see how often we receive
     // empty values.
-    UMA_HISTOGRAM_BOOLEAN("MediaDeviceNotification.MTPDeviceUUIDAvailable",
-                          !device_id.empty());
-    UMA_HISTOGRAM_BOOLEAN("MediaDeviceNotification.MTPDeviceNameAvailable",
-                          !device_name.empty());
-
+    MediaStorageUtil::RecordDeviceInfoHistogram(false, device_id, device_name);
     if (device_id.empty() || device_name.empty())
       return;
 
     DCHECK(!ContainsKey(storage_map_, storage_name));
     storage_map_[storage_name] = device_id;
     system_monitor->ProcessRemovableStorageAttached(device_id, device_name,
                                                     location);
   } else {
     // Existing storage is detached.
     StorageNameToIdMap::iterator it = storage_map_.find(storage_name);
@@ skipping 11 matching lines @@
   DCHECK(mtp_manager);
   StorageList storages = mtp_manager->GetStorages();
   for (StorageList::const_iterator storage_iter = storages.begin();
        storage_iter != storages.end(); ++storage_iter) {
     StorageChanged(true, *storage_iter);
   }
 }
 
 }  // namespace mtp
 }  // namespace chromeos