Update some uses of UTF conversions in chrome/browser to use the base:: namespace.

chrome/browser/storage_monitor/volume_mount_watcher_win.cc

Index: chrome/browser/storage_monitor/volume_mount_watcher_win.cc
diff --git a/chrome/browser/storage_monitor/volume_mount_watcher_win.cc b/chrome/browser/storage_monitor/volume_mount_watcher_win.cc
index ddcc09f5e3f44329f19ebc0bb005c5b108a1c07d..8dd811a43ebab6b02392ffedeb5c889a1b802f4b 100644
--- a/chrome/browser/storage_monitor/volume_mount_watcher_win.cc
+++ b/chrome/browser/storage_monitor/volume_mount_watcher_win.cc
@@ -148,7 +148,7 @@ bool GetDeviceDetails(const base::FilePath& device_path, StorageInfo* info) {
   DeviceType device_type = GetDeviceType(mount_point);
   if (device_type == FLOPPY) {
     info->set_device_id(StorageInfo::MakeDeviceId(
-        StorageInfo::FIXED_MASS_STORAGE, UTF16ToUTF8(guid)));
+        StorageInfo::FIXED_MASS_STORAGE, base::UTF16ToUTF8(guid)));
     return true;
   }
 
@@ -167,7 +167,8 @@ bool GetDeviceDetails(const base::FilePath& device_path, StorageInfo* info) {
                         kMaxPathBufLen, NULL, NULL, NULL, NULL, 0);
 
   uint64 total_size_in_bytes = GetVolumeSize(mount_point);
-  std::string device_id = StorageInfo::MakeDeviceId(type, UTF16ToUTF8(guid));
+  std::string device_id =
+      StorageInfo::MakeDeviceId(type, base::UTF16ToUTF8(guid));
 
   // TODO(gbillock): if volume_label.empty(), get the vendor/model information
   // for the volume.