[GTK] Hide zoom bubble when changing tabs.

This will be a considerably more visible bug when the autoclose timeout is longer.

R=estade@chromium.org
BUG=128070


Review URL: https://chromiumcodereview.appspot.com/10855181

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@151818 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/ui/gtk/location_bar_view_gtk.cc

@@ -669,6 +669,7 @@ void LocationBarViewGtk::Update(const WebContents* contents) {
   } else {
     gtk_widget_queue_draw(widget());
   }
+  ZoomBubbleGtk::Close();
 }
 
 void LocationBarViewGtk::OnAutocompleteAccept(const GURL& url,