Support window.opener after a process swap.

content/browser/renderer_host/test_render_view_host.h

Index: content/browser/renderer_host/test_render_view_host.h
diff --git a/content/browser/renderer_host/test_render_view_host.h b/content/browser/renderer_host/test_render_view_host.h
index a860806c8281d824a66be3b1ce36868e59c0e0cf..37312ccd0e6a974868ff195553e28486c2105d7b 100644
--- a/content/browser/renderer_host/test_render_view_host.h
+++ b/content/browser/renderer_host/test_render_view_host.h
@@ -182,6 +182,9 @@ class TestRenderViewHost : public RenderViewHost {
   void SendNavigateWithTransition(int page_id, const GURL& url,
                                   PageTransition::Type transition);
 
+  // Calls OnMsgShouldCloseACK on the RenderViewHost with the given parameter.
+  void SendShouldCloseACK(bool proceed);
+
   // If set, *delete_counter is incremented when this object destructs.
   void set_delete_counter(int* delete_counter) {
     delete_counter_ = delete_counter;