Make RenderFrameHostManager swap RenderFrameHosts, not RenderViewHosts.

content/browser/frame_host/interstitial_page_impl.h

Index: content/browser/frame_host/interstitial_page_impl.h
diff --git a/content/browser/frame_host/interstitial_page_impl.h b/content/browser/frame_host/interstitial_page_impl.h
index 28d2a0f501389dcf3d5b060b2c7948e759a135f6..a6e95a15302a1ff7d257e30d381a737d375967a4 100644
--- a/content/browser/frame_host/interstitial_page_impl.h
+++ b/content/browser/frame_host/interstitial_page_impl.h
@@ -181,8 +181,8 @@ class CONTENT_EXPORT InterstitialPageImpl
   // - any command sent by the RenderViewHost will be ignored.
   void Disable();
 
-  // Shutdown the RVH.  We will be deleted by the time this method returns.
-  void Shutdown(RenderViewHostImpl* render_view_host);
+  // Delete ourselves, causing Shutdown on the RVH to be called.
+  void Shutdown();
 
   void OnNavigatingAwayOrTabClosing();
 
@@ -230,6 +230,8 @@ class CONTENT_EXPORT InterstitialPageImpl
   // The RenderViewHost displaying the interstitial contents.  This is valid
   // until Hide is called, at which point it will be set to NULL, signifying
   // that shutdown has started.
+  // TODO(creis): This is now owned by the FrameTree.  We should route things
+  // through the tree's root RenderFrameHost instead.
   RenderViewHostImpl* render_view_host_;
 
   // The frame tree structure of the current page.