Remove call of PrerenderTracker::TryCancelOnIOThread in ChromeContentBrowserClient::CanCreateWindow…

chrome/browser/prerender/prerender_contents.cc

Index: chrome/browser/prerender/prerender_contents.cc
===================================================================
--- chrome/browser/prerender/prerender_contents.cc	(revision 243063)
+++ chrome/browser/prerender/prerender_contents.cc	(working copy)
@@ -92,6 +92,21 @@
     callback.Run(false);
   }
 
+   virtual bool ShouldCreateWebContents(
+       WebContents* web_contents,
+       int route_id,
+       WindowContainerType window_container_type,
+       const base::string16& frame_name,
+       const GURL& target_url,
+       const std::string& partition_id,
+       SessionStorageNamespace* session_storage_namespace) OVERRIDE {
+    // Since we don't want to permit child windows that would have a
+    // window.opener property, terminate prerendering.
+    prerender_contents_->Destroy(FINAL_STATUS_CREATE_NEW_WINDOW);
+    // Cancel the popup.
+    return false;

[jochen (gone - plz use gerrit), 2014/01/06 19:37:11]

if you return false here, you need to adopt route_id and
session_storage_namespace.

At this point, the RV is already created, and if you just drop them on the
floor, you'll hit a bunch of checks later on when the RV starts to send IPCs.

[jam, 2014/01/06 21:45:21]

I see, ok thanks, I missed that subtlety.

I've made the content layer handle this, since otherwise every embedder would
have to do this. It's also easier for content to destroy the RenderView since it
has access to these IPCs. Per your comment about background contents, I check
first to see if the RenderViewHost is created, to handle the case where the
embedder returns false but still creates a WebContents.

For the SessionStorageNamespace, the object is deleted after the current method
goes out of scope.

+  }
+
   virtual bool OnGoToEntryOffset(int offset) OVERRIDE {
     // This isn't allowed because the history merge operation
     // does not work if there are renderer issued challenges.