Add ol.source.Tile#getTileGridForProjection

src/ol/source/tilesource.js

@@ -159,6 +159,18 @@ ol.source.Tile.prototype.getTileGrid = function() {
 };
 
 
+/**
+ * @param {ol.proj.Projection} projection Projection.
+ * @return {ol.tilegrid.TileGrid} Tile grid.
+ */
+ol.source.Tile.prototype.getTileGridForProjection = function(projection) {
+  if (goog.isNull(this.tileGrid)) {
+    return ol.tilegrid.getForProjection(projection);
+  } else {
+    return this.tileGrid;
+  }
+
+
 /**
  * Marks a tile coord as being used, without triggering a load.
  * @param {number} z Tile coordinate z.