Only disallow top-level navigations in platform apps

content/renderer/render_view_impl.h

Index: content/renderer/render_view_impl.h
diff --git a/content/renderer/render_view_impl.h b/content/renderer/render_view_impl.h
index 8e5522a2db4342d4d1409dee4717c2177cebe7bd..1d27fcef7b3029da551fd90da7b2c558502726d4 100644
--- a/content/renderer/render_view_impl.h
+++ b/content/renderer/render_view_impl.h
@@ -982,7 +982,12 @@ class RenderViewImpl : public RenderWidget,
   // Returns false unless this is a top-level navigation that crosses origins.
   bool IsNonLocalTopLevelNavigation(const GURL& url,
                                     WebKit::WebFrame* frame,
-                                    WebKit::WebNavigationType type);
+                                    WebKit::WebNavigationType type) const;
+
+  // Returns true if |frame| is the top frame, or if the URL being loaded is
+  // from a different origin than the top frame's.
+  bool IsNonLocalOrTopLevelNavigation(const GURL& url,
+                                      WebKit::WebFrame* frame) const;
 
   bool MaybeLoadAlternateErrorPage(WebKit::WebFrame* frame,
                                    const WebKit::WebURLError& error,