Replace PANGO_IS_RENDERER with PANGO_IS_RENDERER_FAST that is just a

Replace PANGO_IS_RENDERER with PANGO_IS_RENDERER_FAST that is just a

2006-12-04  Behdad Esfahbod  <behdad@gnome.org>

        * pango/pango-renderer.c (pango_renderer_draw_layout_line),
        (pango_renderer_draw_glyphs), (pango_renderer_draw_rectangle),
        (pango_renderer_draw_error_underline),
        (pango_renderer_draw_trapezoid), (pango_renderer_draw_glyph),
        (pango_renderer_activate), (pango_renderer_deactivate),
        (pango_renderer_set_color), (pango_renderer_get_color),
        (pango_renderer_part_changed), (pango_renderer_prepare_run),
        (pango_renderer_set_matrix): Replace PANGO_IS_RENDERER with
        PANGO_IS_RENDERER_FAST that is just a NULL-check.