Fix stride related bug in Canvas immediate API

src/ol/geom/flat/transformflatgeom.js

@@ -5,13 +5,15 @@ goog.require('goog.vec.Mat4');
 
 /**
  * @param {Array.<number>} flatCoordinates Flat coordinates.
+ * @param {number} offset Offset.
+ * @param {number} end End.
  * @param {number} stride Stride.
  * @param {goog.vec.Mat4.Number} transform Transform.
  * @param {Array.<number>=} opt_dest Destination.
  * @return {Array.<number>} Transformed coordinates.
  */
 ol.geom.flat.transform.transform2D =
-    function(flatCoordinates, stride, transform, opt_dest) {
+    function(flatCoordinates, offset, end, stride, transform, opt_dest) {
   var m00 = goog.vec.Mat4.getElement(transform, 0, 0);
   var m10 = goog.vec.Mat4.getElement(transform, 1, 0);
   var m01 = goog.vec.Mat4.getElement(transform, 0, 1);
@@ -21,7 +23,7 @@ ol.geom.flat.transform.transform2D =
   var dest = goog.isDef(opt_dest) ? opt_dest : [];
   var i = 0;
   var j, jj;
-  for (j = 0, jj = flatCoordinates.length; j < jj; j += stride) {
+  for (j = offset; j < end; j += stride) {
     var x = flatCoordinates[j];
     var y = flatCoordinates[j + 1];
     dest[i++] = m00 * x + m01 * y + m03;

src/ol/geom/simplegeometry.js

@@ -269,6 +269,7 @@ ol.geom.transformSimpleGeometry2D =
   } else {
     var stride = simpleGeometry.getStride();
     return ol.geom.flat.transform.transform2D(
-        flatCoordinates, stride, transform, opt_dest);
+        flatCoordinates, 0, flatCoordinates.length, stride,
+        transform, opt_dest);
   }
 };