Pass pixel ratio to ol.render.canvas.Immediate constructor

src/ol/render/canvas/canvasimmediate.js

@@ -17,11 +17,12 @@ goog.require('ol.style.Text');
  * @constructor
  * @implements {ol.render.IRender}
  * @param {CanvasRenderingContext2D} context Context.
+ * @param {number} pixelRatio Pixel ratio.
  * @param {ol.Extent} extent Extent.
  * @param {goog.vec.Mat4.AnyType} transform Transform.
  * @struct
  */
-ol.render.canvas.Immediate = function(context, extent, transform) {
+ol.render.canvas.Immediate = function(context, pixelRatio, extent, transform) {
 
   /**
    * @private
@@ -29,6 +30,12 @@ ol.render.canvas.Immediate = function(context, extent, transform) {
    */
   this.context_ = context;
 
+  /**
+   * @private
+   * @type {number}
+   */
+  this.pixelRatio_ = pixelRatio;
+
   /**
    * @private
    * @type {ol.Extent}