Prevent drag-and-drop events from firing over cross-site, same-page frames. (Mac)

content/browser/web_contents/web_contents_view_mac.mm

 // Copyright (c) 2012 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 <Carbon/Carbon.h>
 
 #import "content/browser/web_contents/web_contents_view_mac.h"
 
 #include <string>
 
@@ skipping 531 matching lines @@
                              forType:type];
 }
 
 - (void)startDragWithDropData:(const DropData&)dropData
                     sourceRWH:(content::RenderWidgetHostImpl*)sourceRWH
             dragOperationMask:(NSDragOperation)operationMask
                         image:(NSImage*)image
                        offset:(NSPoint)offset {
   if (![self webContents])
     return;
+  [dragDest_ setDragStartTrackersForProcess:sourceRWH->GetProcess()->GetID()];
   dragSource_.reset([[WebDragSource alloc]
        initWithContents:[self webContents]
                    view:self
                dropData:&dropData
               sourceRWH:sourceRWH
                   image:image
                  offset:offset
              pasteboard:[NSPasteboard pasteboardWithName:NSDragPboard]
       dragOperationMask:operationMask]);
   [dragSource_ startDrag];
@@ skipping 161 matching lines @@
 
 - (void)viewDidHide {
   [self updateWebContentsVisibility];
 }
 
 - (void)viewDidUnhide {
   [self updateWebContentsVisibility];
 }
 
 @end