Make it so that allow_js_access: false can be used with background pages created by window.open.

content/public/browser/content_browser_client.h

Index: content/public/browser/content_browser_client.h
diff --git a/content/public/browser/content_browser_client.h b/content/public/browser/content_browser_client.h
index c9303d93a919ac054531146147151a5625e623ee..fcff765f5d1912de1aef4cb0e8a6a2b0b1816443 100644
--- a/content/public/browser/content_browser_client.h
+++ b/content/public/browser/content_browser_client.h
@@ -91,6 +91,12 @@ class ContentBrowserClient {
  public:
   virtual ~ContentBrowserClient() {}
 
+  enum CanCreateWindowResult {
+    CANNOT_CREATE_WINDOW,
+    CAN_CREATE_WINDOW,
+    CAN_CREATE_WINDOW_NO_JS_ACCESS
+  };
+
   // Allows the embedder to set any number of custom BrowserMainParts
   // implementations for the browser startup code. See comments in
   // browser_main_parts.h.
@@ -333,7 +339,7 @@ class ContentBrowserClient {
   // Returns true if the given page is allowed to open a window of the given
   // type.
   // This is called on the IO thread.
-  virtual bool CanCreateWindow(
+  virtual CanCreateWindowResult CanCreateWindow(
       const GURL& opener_url,
       const GURL& source_origin,
       WindowContainerType container_type,