Push one function from the Mac drag/drop util code to ui/.

chrome/browser/ui/cocoa/url_drop_target.mm

 // Copyright (c) 2011 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.
 
 #import "chrome/browser/ui/cocoa/url_drop_target.h"
 
 #include "base/basictypes.h"
 #include "chrome/browser/ui/cocoa/drag_util.h"
+#include "googleurl/src/gurl.h"
 #import "third_party/mozilla/NSPasteboard+Utils.h"
 
 @interface URLDropTargetHandler(Private)
 
 // Gets the appropriate drag operation given the |NSDraggingInfo|.
 - (NSDragOperation)getDragOperation:(id<NSDraggingInfo>)sender;
 
 // Tell the window controller to hide the drop indicator.
 - (void)hideIndicator;
 
@@ skipping 97 matching lines @@
 
   // Only allow the copy operation.
   return [sender draggingSourceOperationMask] & NSDragOperationCopy;
 }
 
 - (void)hideIndicator {
   [[view_ urlDropController] hideDropURLsIndicatorInView:view_];
 }
 
 @end  // @implementation URLDropTargetHandler(Private)