[Media Galleries] Lazily initialize the storage monitor.

chrome/browser/media_galleries/media_galleries_dialog_controller.h

Index: chrome/browser/media_galleries/media_galleries_dialog_controller.h
diff --git a/chrome/browser/media_galleries/media_galleries_dialog_controller.h b/chrome/browser/media_galleries/media_galleries_dialog_controller.h
index bc42f9451b75faa9b091813c6c65741860aa1a72..72921b858a4d7bb2de0b08edc3f05aac3f089579 100644
--- a/chrome/browser/media_galleries/media_galleries_dialog_controller.h
+++ b/chrome/browser/media_galleries/media_galleries_dialog_controller.h
@@ -125,6 +125,10 @@ class MediaGalleriesDialogController
   typedef std::map<MediaGalleryPrefId, GalleryPermission>
       KnownGalleryPermissions;
 
+  // Bottom half of constructor -- called when the storage monitor
+  // is initialized.
+  void OnStorageMonitorInitialized();
+
   // SelectFileDialog::Listener implementation:
   virtual void FileSelected(const base::FilePath& path,
                             int index,
@@ -191,6 +195,8 @@ class MediaGalleriesDialogController
 
   scoped_refptr<ui::SelectFileDialog> select_folder_dialog_;
 
+  base::WeakPtrFactory<MediaGalleriesDialogController> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaGalleriesDialogController);
 };