Move configuration of maximum tiles loading into map.js

src/ol/map.js

@@ -77,6 +77,12 @@ ol.ENABLE_DOM = true;
 ol.ENABLE_WEBGL = true;
 
 
+/**
+ * @define {number} Maximum number of simultaneously loading tiles.
+ */
+ol.MAXIMUM_TILES_LOADING = 8;
+
+
 /**
  * @define {number} Maximum new tile loads per frame.
  */
@@ -279,7 +285,9 @@ ol.Map = function(mapOptions) {
    * @private
    * @type {ol.TileQueue}
    */
-  this.tileQueue_ = new ol.TileQueue(goog.bind(this.getTilePriority, this),
+  this.tileQueue_ = new ol.TileQueue(
+      ol.MAXIMUM_TILES_LOADING,
+      goog.bind(this.getTilePriority, this),
       goog.bind(this.handleTileChange_, this));
 
   goog.events.listen(this, ol.Object.getChangedEventType(ol.MapProperty.VIEW),