Refactor to a more convenient internal API

src/ol/render.js

@@ -1,6 +1,6 @@
 goog.provide('ol.render');
 
-goog.require('ol.matrix');
+goog.require('ol.transform');
 goog.require('ol.render.canvas.Immediate');
 
 
@@ -36,8 +36,7 @@ ol.render.toContext = function(context, opt_options) {
     canvas.style.height = size[1] + 'px';
   }
   var extent = [0, 0, canvas.width, canvas.height];
-  var transform = ol.matrix.makeTransform(ol.matrix.create(),
-      0, 0, pixelRatio, pixelRatio, 0, 0, 0);
+  var transform = ol.transform.scale(ol.transform.create(), pixelRatio, pixelRatio);
   return new ol.render.canvas.Immediate(context, pixelRatio, extent, transform,
       0);
 };