making pink tiles a css matter. p=rdewit, r=me (closes #2318)

git-svn-id: http://svn.openlayers.org/trunk/openlayers@9758 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

examples/regular-polygons.html

@@ -28,11 +28,15 @@
             margin-left: 15em;
             position: absolute;
         }
+
+        /* avoid pink tiles */
+        .olImageLoadError {
+            background-color: transparent !important;
+        }
     </style>
     <script src="../lib/OpenLayers.js"></script>
     <script type="text/javascript">
         var map, polygonControl;
-        OpenLayers.Util.onImageLoadErrorColor = "transparent";
         function init(){
             map = new OpenLayers.Map('map');