Extract minimal RenderViewHost interface for embedders, leaving

content/browser/tab_contents/web_drag_source_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 "content/browser/tab_contents/web_drag_source_mac.h"
 
 #include <sys/param.h>
 
 #include "base/bind.h"
 #include "base/file_path.h"
@@ skipping 243 matching lines @@
               event:dragEvent
          pasteboard:pasteboard_
              source:contentsView_
           slideBack:YES];
 }
 
 - (void)endDragAt:(NSPoint)screenPoint
         operation:(NSDragOperation)operation {
   contents_->SystemDragEnded();
 
-  RenderViewHost* rvh = contents_->GetRenderViewHost();
+  RenderViewHostImpl* rvh = static_cast<RenderViewHostImpl*>(
+      contents_->GetRenderViewHost());
   if (rvh) {
     // Convert |screenPoint| to view coordinates and flip it.
     NSPoint localPoint = NSMakePoint(0, 0);
     if ([contentsView_ window])
       localPoint = [self convertScreenPoint:screenPoint];
     NSRect viewFrame = [contentsView_ frame];
     localPoint.y = viewFrame.size.height - localPoint.y;
     // Flip |screenPoint|.
     NSRect screenFrame = [[[contentsView_ window] screen] frame];
     screenPoint.y = screenFrame.size.height - screenPoint.y;
 
     // If AppKit returns a copy and move operation, mask off the move bit
     // because WebCore does not understand what it means to do both, which
     // results in an assertion failure/renderer crash.
     if (operation == (NSDragOperationMove | NSDragOperationCopy))
       operation &= ~NSDragOperationMove;
 
     rvh->DragSourceEndedAt(localPoint.x, localPoint.y,
                            screenPoint.x, screenPoint.y,
                            static_cast<WebKit::WebDragOperation>(operation));
   }
 
   // Make sure the pasteboard owner isn't us.
   [pasteboard_ declareTypes:[NSArray array] owner:nil];
 }
 
 - (void)moveDragTo:(NSPoint)screenPoint {
-  RenderViewHost* rvh = contents_->GetRenderViewHost();
+  RenderViewHostImpl* rvh = static_cast<RenderViewHostImpl*>(
+      contents_->GetRenderViewHost());
   if (rvh) {
     // Convert |screenPoint| to view coordinates and flip it.
     NSPoint localPoint = NSMakePoint(0, 0);
     if ([contentsView_ window])
       localPoint = [self convertScreenPoint:screenPoint];
     NSRect viewFrame = [contentsView_ frame];
     localPoint.y = viewFrame.size.height - localPoint.y;
     // Flip |screenPoint|.
     NSRect screenFrame = [[[contentsView_ window] screen] frame];
     screenPoint.y = screenFrame.size.height - screenPoint.y;
@@ skipping 138 matching lines @@
 
 - (NSImage*)dragImage {
   if (dragImage_)
     return dragImage_;
 
   // Default to returning a generic image.
   return gfx::GetCachedImageWithName(@"nav.pdf");
 }
 
 @end  // @implementation WebDragSource (Private)