DO NOT COMMIT: Revert "Enable subframe FrameNavigationEntries by default."

content/browser/web_contents/web_contents_impl.cc

 // 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.
 
 #include "content/browser/web_contents/web_contents_impl.h"
 
 #include <stddef.h>
 
 #include <cmath>
 #include <utility>
@@ skipping 4286 matching lines @@
 void WebContentsImpl::UpdateState(RenderViewHost* rvh,
                                   const PageState& page_state) {
   DCHECK(!SiteIsolationPolicy::UseSubframeNavigationEntries());
 
   // Ensure that this state update comes from a RenderViewHost that belongs to
   // this WebContents.
   // TODO(nasko): This should go through RenderFrameHost.
   if (rvh->GetDelegate()->GetAsWebContents() != this)
     return;
 
-  if (!rvh->GetMainFrame()) {
-    // When UseSubframeNavigationEntries is turned off, state updates only come
-    // in on main frames. When UseSubframeNavigationEntries is turned on,
-    // UpdateStateForFrame() should have been called rather than this function.
-    NOTREACHED();
+  if (!rvh->GetMainFrame())
     return;
-  }
 
   NavigationEntryImpl* entry = controller_.GetEntryWithUniqueID(
       static_cast<RenderFrameHostImpl*>(rvh->GetMainFrame())->nav_entry_id());
+  if (!entry)
+    return;
 
   if (page_state == entry->GetPageState())
     return;  // Nothing to update.
   entry->SetPageState(page_state);
   controller_.NotifyEntryChanged(entry);
 }
 
 void WebContentsImpl::UpdateTargetURL(RenderViewHost* render_view_host,
                                       const GURL& url) {
   if (fullscreen_widget_routing_id_ != MSG_ROUTING_NONE) {
@@ skipping 869 matching lines @@
   dialog_manager_ = dialog_manager;
 }
 
 void WebContentsImpl::RemoveBindingSet(const std::string& interface_name) {
   auto it = binding_sets_.find(interface_name);
   if (it != binding_sets_.end())
     binding_sets_.erase(it);
 }
 
 }  // namespace content