Make browser_handles_top_level_requests synchronous.

chrome/browser/external_tab/external_tab_container_win.h

Index: chrome/browser/external_tab/external_tab_container_win.h
diff --git a/chrome/browser/external_tab/external_tab_container_win.h b/chrome/browser/external_tab/external_tab_container_win.h
index ed6f20fa92b4bbf47efcf880e2cbd91a701d7bd4..53bf457b6c7a064f3fcab811afc728e4db8ec72c 100644
--- a/chrome/browser/external_tab/external_tab_container_win.h
+++ b/chrome/browser/external_tab/external_tab_container_win.h
@@ -122,6 +122,13 @@ class ExternalTabContainer : public content::WebContentsDelegate,
   virtual content::WebContents* OpenURLFromTab(
       content::WebContents* source,
       const content::OpenURLParams& params) OVERRIDE;
+  virtual bool ShouldIgnoreNavigation(
+      content::WebContents* source,
+      const GURL& url,
+      const content::Referrer& referrer,
+      WindowOpenDisposition disposition,
+      bool is_content_initiated,
+      content::PageTransition transition_type) OVERRIDE;
   virtual void NavigationStateChanged(const content::WebContents* source,
                                       unsigned changed_flags) OVERRIDE;
   virtual void AddNewContents(content::WebContents* source,