Ensure that before creating proxy of site A, RVH of site A is initialized.

content/browser/frame_host/render_frame_host_manager.h

Index: content/browser/frame_host/render_frame_host_manager.h
diff --git a/content/browser/frame_host/render_frame_host_manager.h b/content/browser/frame_host/render_frame_host_manager.h
index cc2e2d840dc57bf92d32d53b482e66d46a4b613a..518890125979f8892294f929a6284ad40bf54412 100644
--- a/content/browser/frame_host/render_frame_host_manager.h
+++ b/content/browser/frame_host/render_frame_host_manager.h
@@ -397,6 +397,10 @@ class CONTENT_EXPORT RenderFrameHostManager : public NotificationObserver {
   void OnDidStartLoading();
   void OnDidStopLoading();
 
+  void EnsureRenderViewInitialized(FrameTreeNode* source,
+                                   RenderViewHostImpl* render_view_host,
+                                   SiteInstance* instance);
+
  private:
   friend class NavigatorTestWithBrowserSideNavigation;
   friend class RenderFrameHostManagerTest;
@@ -409,6 +413,10 @@ class CONTENT_EXPORT RenderFrameHostManager : public NotificationObserver {
   // FrameTreeNode's RenderFrameHostManager.
   static bool ClearProxiesInSiteInstance(int32 site_instance_id,
                                          FrameTreeNode* node);
+  // Used with FrameTree::ForEach to reset initialized state of
+  // RenderFrameProxyHosts from a FrameTreeNode's RenderFrameHostManager.
+  static bool ResetProxiesInSiteInstance(int32 site_instance_id,
+                                         FrameTreeNode* node);
 
   // Returns whether this tab should transition to a new renderer for
   // cross-site URLs.  Enabled unless we see the --process-per-tab command line