Don't set the canvas size too early

src/ol/renderer/webgl/webglmaprenderer.js

@@ -71,8 +71,6 @@ ol.renderer.webgl.Map = function(container, map) {
    */
   this.canvas_ = /** @type {HTMLCanvasElement} */
       (goog.dom.createElement(goog.dom.TagName.CANVAS));
-  this.canvas_.height = container.clientHeight;
-  this.canvas_.width = container.clientWidth;
   this.canvas_.className = ol.css.CLASS_UNSELECTABLE;
   goog.dom.insertChildAt(container, this.canvas_, 0);