remove uneeded default cases

include/mapnik/image_compositing.hpp

@@ -172,9 +172,6 @@ void composite(T1 & im, T2 & im2, composite_mode_e mode)
     case invert_rgb:
         pixf.comp_op(agg::comp_op_invert_rgb);
         break;
-    default:
-        break;
-
     }
     renderer_type ren(pixf);
     agg::renderer_base<pixfmt_type> rb(pixf);

include/mapnik/raster_symbolizer.hpp

@@ -131,9 +131,6 @@ struct MAPNIK_DECL raster_symbolizer : public symbolizer_base
             case SCALING_BLACKMAN:
                 ff = 2.0;
                 break;
-            default:
-                ff = 1.0;
-                break;
             }
             return ff;
         }