Drag-and-drop: Target drag messages to specific RenderWidgets.

content/browser/web_contents/web_contents_view_child_frame.h

 // Copyright (c) 2016 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 CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_VIEW_CHILD_FRAME_H_
 #define CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_VIEW_CHILD_FRAME_H_
 
 #include "base/macros.h"
 #include "content/browser/renderer_host/render_view_host_delegate_view.h"
 #include "content/browser/web_contents/web_contents_view.h"
@@ skipping 43 matching lines @@
   void CloseTabAfterEventTracking() override;
 #endif
 
   // Backend implementation of RenderViewHostDelegateView.
   void ShowContextMenu(RenderFrameHost* render_frame_host,
                        const ContextMenuParams& params) override;
   void StartDragging(const DropData& drop_data,
                      blink::WebDragOperationsMask allowed_ops,
                      const gfx::ImageSkia& image,
                      const gfx::Vector2d& image_offset,
-                     const DragEventSourceInfo& event_info) override;
+                     const DragEventSourceInfo& event_info,
+                     RenderWidgetHostImpl* source_rwh) override;
   void UpdateDragCursor(blink::WebDragOperation operation) override;
   void GotFocus() override;
   void TakeFocus(bool reverse) override;
 
  private:
   WebContentsView* GetOuterView();
   const WebContentsView* GetOuterView() const;
 
   // The WebContentsImpl whose contents we display.
   WebContentsImpl* web_contents_;
 
   // The delegate ownership is passed to WebContentsView.
   std::unique_ptr<WebContentsViewDelegate> delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsViewChildFrame);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_VIEW_CHILD_FRAME_H_