Remove touch events from Sky

We use pointer events instead.

R=esprehn@chromium.org

Review URL: https://codereview.chromium.org/868133003

examples/touch-demo.sky

@@ -15,22 +15,20 @@ dot {
 var dot = document.querySelector("dot");
 var log = document.querySelector("log");
 
-function logTouchEvent(evt) {
+function logPointerEvent(evt) {
   var message = "type=" + event.type;
-  if (evt.touches && evt.touches.length > 0) {
-    var x = evt.touches[0].clientX.toFixed(2);
-    var y = evt.touches[0].clientY.toFixed(2);
-    message += " x=" + x + " y=" + y;
+  var x = evt.x.toFixed(2);
+  var y = evt.y.toFixed(2);
+  message += " x=" + x + " y=" + y;
 
-    var transform = "translate(" + (x - 50)  + "px," + (y - 50) + "px)";
-    dot.style.transform = transform;
-  }
+  var transform = "translate(" + (x - 50)  + "px," + (y - 50) + "px)";
+  dot.style.transform = transform;
   log.textContent = message;
 }
 
-document.documentElement.addEventListener("touchstart", logTouchEvent);
-document.documentElement.addEventListener("touchmove", logTouchEvent);
-document.documentElement.addEventListener("touchend", logTouchEvent);
-document.documentElement.addEventListener("touchcancel", logTouchEvent);
+document.documentElement.addEventListener("pointerdown", logPointerEvent);
+document.documentElement.addEventListener("pointermove", logPointerEvent);
+document.documentElement.addEventListener("pointerup", logPointerEvent);
+document.documentElement.addEventListener("pointercancel", logPointerEvent);
 </script>
 </sky>