GTK: Drags of images should have titles instead of "".

app/gtk_dnd_util.h

 // Copyright (c) 2009 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.
 
 #ifndef APP_GTK_DND_UTIL_H_
 #define APP_GTK_DND_UTIL_H_
 #pragma once
 
 #include <gtk/gtk.h>
 
@@ skipping 46 matching lines @@
 // corresponds to |code_mask|.
 void SetSourceTargetListFromCodeMask(GtkWidget* source, int code_mask);
 
 // Set the accepted targets list for |dest|. The |target_codes| array should
 // be sorted in preference order and should be terminated with -1.
 void SetDestTargetList(GtkWidget* dest, const int* target_codes);
 
 // Write a URL to the selection in the given type.
 void WriteURLWithName(GtkSelectionData* selection_data,
                       const GURL& url,
-                      const string16& title,
+                      string16 title,
                       int type);
 
 // Extracts data of type CHROME_NAMED_URL from |selection_data| into
 // |url| and |title|. Returns true if the url/title were safely extracted
 // and the url is valid.
 bool ExtractNamedURL(GtkSelectionData* selection_data,
                      GURL* url,
                      string16* title);
 
 // Extracts data of type TEXT_URI_LIST from |selection_data| into |urls|.
 bool ExtractURIList(GtkSelectionData* selection_data,
                     std::vector<GURL>* urls);
 
 }  // namespace gtk_dnd_util
 
 #endif  // APP_GTK_DND_UTIL_H_