Don't search entire row list twice for element being removed.

Don't search entire row list twice for element being removed.

        * gtk/gtkclist.c (real_remove_row):
        Don't search entire row list twice for element being removed.

        * gtk/gtkmenushell.c (gtk_menu_shell_insert):
        Replaced hand-coded implementation of g_list_insert with
        call to g_list_insert.

        * gtk/gtktooltips.c
          (gtk_tooltips_destroy_data, gtk_tooltips_layout_text):
        tooltipsdata->row test not-null test now properly encompasses
        both g_list_* calls.