Media Galleries: Use the same last directory entry as file_system_api.

chrome/browser/media_galleries/media_galleries_dialog_controller.h

Index: chrome/browser/media_galleries/media_galleries_dialog_controller.h
===================================================================
--- chrome/browser/media_galleries/media_galleries_dialog_controller.h	(revision 232670)
+++ chrome/browser/media_galleries/media_galleries_dialog_controller.h	(working copy)
@@ -30,6 +30,7 @@
 
 class GalleryContextMenuModel;
 class MediaGalleriesDialogController;
+class Profile;
 
 // The view.
 class MediaGalleriesDialog {
@@ -167,6 +168,8 @@
   void FillPermissions(bool attached,
                        GalleryPermissionsVector* permissions) const;
 
+  Profile* GetProfile();
+
   // The web contents from which the request originated.
   content::WebContents* web_contents_;