A bunch more source file reorganisations

Part one

core/modules/utils/dom/scroller.js

@@ -0,0 +1,59 @@
+/*\
+title: $:/core/modules/scroller.js
+type: application/javascript
+module-type: utils
+
+Plugin that creates a $tw.utils.Scroller object prototype that manages scrolling in the browser
+
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+var slowInSlowOut = function(t) {
+	return (1 - ((Math.cos(t * Math.PI) + 1) / 2));
+};
+
+/*
+Creates a Scroller object
+*/
+var Scroller = function() {
+};
+
+Scroller.prototype.cancel = function() {
+	if(this.timerId) {
+		window.clearInterval(this.timerId);
+		this.timerId = null;
+	}
+};
+
+/*
+Smoothly scroll an element back into view if needed
+*/
+Scroller.prototype.scrollIntoView = function(element) {
+	var scrollPosition = $tw.utils.getScrollPosition();
+	this.cancel();
+	this.startTime = new Date();
+	this.startX = scrollPosition.x;
+	this.startY = scrollPosition.y;
+	this.endX = element.offsetLeft;
+	this.endY = element.offsetTop;
+	if((this.endX < this.startX) || (this.endX > (this.startX + window.innerWidth)) || (this.endY < this.startY) || (this.endY > (this.startY + window.innerHeight))) {
+		var self = this;
+		this.timerId = window.setInterval(function() {
+			var t = ((new Date()) - self.startTime) / $tw.config.preferences.animationDuration;
+			if(t >= 1) {
+				self.cancel();
+				t = 1;
+			}
+			t = slowInSlowOut(t);
+			window.scrollTo(self.startX + (self.endX - self.startX) * t,self.startY + (self.endY - self.startY) * t);
+		}, 10);
+	}
+};
+
+exports.Scroller = Scroller;
+
+})();