fixed loading forever on torque visualizations

lib/torque/leaflet/leaflet_tileloader_mixin.js

@@ -80,11 +80,12 @@ L.Mixin.TileLoader = {
   },
 
   _removeOtherTiles: function (bounds) {
+      var self = this;
       var kArr, x, y, z, key;
       var zoom = this._map.getZoom();
       
-      for (key in this._tiles) {
+      function checkTile(c, key) {
-          if (this._tiles.hasOwnProperty(key)) {
+          if (c.hasOwnProperty(key)) {
               kArr = key.split(':');
               x = parseInt(kArr[0], 10);
               y = parseInt(kArr[1], 10);
@@ -92,22 +93,41 @@ L.Mixin.TileLoader = {
 
               // remove tile if it's out of bounds
               if (zoom !== z || x < bounds.min.x || x > bounds.max.x || y < bounds.min.y || y > bounds.max.y) {
-                  this._removeTile(key);
+                  self._removeTile(key);
               }
           }
       }
+
+      for (key in this._tiles) {
+        checkTile(this._tiles, key);
+      }
+      for (key in this._tilesLoading) {
+        checkTile(this._tilesLoading, key);
+      }
   },
 
   _removeTile: function (key) {
       this.fire('tileRemoved', this._tiles[key]);
       delete this._tiles[key];
-      delete this._tilesLoading[key];
+      if (this._tilesLoading[key]) {
+        --this._tilesToLoad;
+        delete this._tilesLoading[key];
+      }
   },
 
   _tileKey: function(tilePoint) {
     return tilePoint.x + ':' + tilePoint.y + ':' + tilePoint.zoom;
   },
 
+  _tileFromKey: function(key) {
+      var kArr = key.split(':');
+      return {
+        x: parseInt(kArr[0], 10),
+        y: parseInt(kArr[1], 10),
+        z: parseInt(kArr[2], 10)
+      }
+  },
+
   _tileShouldBeLoaded: function (tilePoint) {
       var k = this._tileKey(tilePoint);
       return !(k in this._tiles) && !(k in this._tilesLoading);