[WebUI] ClosureCompile cr.ui.DragWrapper, create a real handler class

chrome/browser/resources/ntp4/tile_page.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 cr.define('ntp', function() {
   'use strict';
 
   // We can't pass the currently dragging tile via dataTransfer because of
   // http://crbug.com/31037
   var currentlyDraggingTile = null;
@@ skipping 341 matching lines @@
   // the tile page padding.
   var MIN_WIDE_MARGIN = 18;
 
   /**
    * Creates a new TilePage object. This object contains tiles and controls
    * their layout.
    * @param {Object} gridValues Pixel values that define the size and layout
    *     of the tile grid.
    * @constructor
    * @extends {HTMLDivElement}
+   * @implements {cr.ui.DragWrapperDelegate}
    */
   function TilePage(gridValues) {
     var el = cr.doc.createElement('div');
     el.gridValues_ = gridValues;
     el.__proto__ = TilePage.prototype;
     el.initialize();
 
     return el;
   }
 
@@ skipping 766 matching lines @@
     heightForWidth: function(width) {
       return width;
     },
 
     /** Dragging **/
 
     get isCurrentDragTarget() {
       return this.dragWrapper_.isCurrentDragTarget;
     },
 
-    /**
-     * Thunk for dragleave events fired on |tileGrid_|.
-     * @param {Event} e A MouseEvent for the drag.
-     */
+    /** @override */
     doDragLeave: function(e) {
       this.cleanupDrag();
     },
 
-    /**
-     * Performs all actions necessary when a drag enters the tile page.
-     * @param {Event} e A mouseover event for the drag enter.
-     */
+    /** @override */
     doDragEnter: function(e) {
       // Applies the mask so doppleganger tiles disappear into the fog.
       this.updateMask_();
 
       this.classList.add('animating-tile-page');
       this.withinPageDrag_ = this.contains(currentlyDraggingTile);
       this.dragItemIndex_ = this.withinPageDrag_ ?
           currentlyDraggingTile.index : this.tileElements_.length;
       this.currentDropIndex_ = this.dragItemIndex_;
 
       // The new tile may change the number of rows, hence the top margin
       // will change.
       if (!this.withinPageDrag_)
         this.updateTopMargin_();
 
       this.doDragOver(e);
     },
 
-    /**
-     * Performs all actions necessary when the user moves the cursor during
-     * a drag over the tile page.
-     * @param {Event} e A mouseover event for the drag over.
-     */
+    /** @override */
     doDragOver: function(e) {
       e.preventDefault();
 
       this.setDropEffect(e.dataTransfer);
       var newDragIndex = this.getWouldBeIndexForPoint_(e.pageX, e.pageY);
       if (newDragIndex < 0 || newDragIndex >= this.tileElements_.length)
         newDragIndex = this.dragItemIndex_;
       this.updateDropIndicator_(newDragIndex);
     },
 
-    /**
-     * Performs all actions necessary when the user completes a drop.
-     * @param {Event} e A mouseover event for the drag drop.
-     */
+    /** @override */
     doDrop: function(e) {
       e.stopPropagation();
       e.preventDefault();
 
       var index = this.currentDropIndex_;
       // Only change data if this was not a 'null drag'.
       if (!((index == this.dragItemIndex_) && this.withinPageDrag_)) {
         var adjustedIndex = this.currentDropIndex_ +
             (index > this.dragItemIndex_ ? 1 : 0);
         if (this.withinPageDrag_) {
@@ skipping 120 matching lines @@
   };
 
   return {
     getCurrentlyDraggingTile: getCurrentlyDraggingTile,
     setCurrentDropEffect: setCurrentDropEffect,
     // Not used outside, just for usage in JSDoc inside this file.
     Tile: Tile,
     TilePage: TilePage,
   };
 });