Tests that the title only ever gets replaced for the current page.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 2e6a5f7556dd8378d2b796a9d676fa9c9ce0472c..8d60762d70c490a91d04af161250153c78f2d165 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -3868,6 +3868,11 @@ void WebContentsImpl::UpdateTitle(RenderFrameHost* render_frame_host,
   NavigationEntryImpl* entry = controller_.GetEntryWithPageID(
       rvh->GetSiteInstance(), page_id);
 
+  // Re http://crbug.com/369661, page id is going away. This function should
+  // only ever be called for the last committed entry. When this is verified,
+  // this function can be greatly simplified.
+  CHECK_EQ(entry, controller_.GetLastCommittedEntry());
+
   // We can handle title updates when we don't have an entry in
   // UpdateTitleForEntry, but only if the update is from the current RVH.
   // TODO(avi): Change to make decisions based on the RenderFrameHost.