GTK: Fix a couple minor popup window icon menu bugs.

BUG=26265,26268

Review URL: http://codereview.chromium.org/360023

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@31009 0039d316-1c4b-4281-b951-d872f2087c98
void MenuGtk::PopupAsFromKeyEvent(GtkWidget* widget) {
  Popup(widget, 0, gtk_get_current_event_time());
  gtk_menu_shell_select_first(GTK_MENU_SHELL(menu_.get()), FALSE);
}

void MenuGtk::PopupAsFromKeyEvent(GtkWidget* widget) {
  Popup(widget, 0, gtk_get_current_event_time());
  gtk_menu_shell_select_first(GTK_MENU_SHELL(menu_.get()), FALSE);
}
