Give prerendering RVH's RenderWidgetHostViews.

content/browser/tab_contents/render_view_host_manager.cc

 // 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.
 
 #include "content/browser/tab_contents/render_view_host_manager.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_switches.h"
@@ skipping 673 matching lines @@
   web_ui_.reset();
 
   // Hide the current view and prepare to destroy it.
   if (render_view_host_->view())
     render_view_host_->view()->Hide();
   RenderViewHost* old_render_view_host = render_view_host_;
 
   // Swap in the new view and make it active.
   render_view_host_ = rvh;
   render_view_host_->set_delegate(render_view_delegate_);
+  // Remove old RenderWidgetHostView with mocked out methods so it can be
+  // replaced with a new one that's a child of |delegate_|'s view.
+  scoped_ptr<RenderWidgetHostView> old_view(render_view_host_->view());
+  render_view_host_->set_view(NULL);
   delegate_->CreateViewAndSetSizeForRVH(render_view_host_);
   render_view_host_->ActivateDeferredPluginHandles();
   // If the view is gone, then this RenderViewHost died while it was hidden.
   // We ignored the RenderViewGone call at the time, so we should send it now
   // to make sure the sad tab shows up, etc.
   if (render_view_host_->view()) {
-    // TODO(tburkard,cbentzel): Figure out why this hack is needed and/or
-    // if it can be removed.  On Windows, prerendering will not work without
-    // doing a Hide before the Show.
+    // The Hide() is needed to sync the state of |render_view_host_|, which is
+    // hidden, with the newly created view, which does not know the
+    // RenderViewHost is hidden.
+    // TODO(tburkard,cbentzel): Figure out if this hack can be removed
+    //                          (http://crbug.com/79891).
     render_view_host_->view()->Hide();
     render_view_host_->view()->Show();
   }
 
   delegate_->UpdateRenderViewSizeForRenderManager();
 
   RenderViewHostSwitchedDetails details;
   details.new_host = render_view_host_;
   details.old_host = old_render_view_host;
   NotificationService::current()->Notify(
       NotificationType::RENDER_VIEW_HOST_CHANGED,
       Source<NavigationController>(&delegate_->GetControllerForRenderManager()),
       Details<RenderViewHostSwitchedDetails>(&details));
 
   // This will cause the old RenderViewHost to delete itself.
   old_render_view_host->Shutdown();
 
   // Let the task manager know that we've swapped RenderViewHosts, since it
   // might need to update its process groupings.
   delegate_->NotifySwappedFromRenderManager();
 }