Fire visibilityChange event on out-of-process iframes.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index c49d37d16639fb29665be9c3acad59d8eded955a..bbdef7a70a14ff749dbd5068bd4dac3f7b97ecf0 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -1314,6 +1314,8 @@ void WebContentsImpl::WasShown() {
     }
   }
 
+  SendPageMessage(new PageMsg_WasShown(MSG_ROUTING_NONE));
+
   last_active_time_ = base::TimeTicks::Now();
 
   // The resize rect might have changed while this was inactive -- send the new
@@ -1343,6 +1345,8 @@ void WebContentsImpl::WasHidden() {
       if (view)
         view->Hide();
     }
+
+    SendPageMessage(new PageMsg_WasHidden(MSG_ROUTING_NONE));
   }
 
   FOR_EACH_OBSERVER(WebContentsObserver, observers_, WasHidden());