ntp4: make app-install-via-drag less janky

chrome/browser/resources/ntp4/apps_page.js

 // Copyright (c) 2011 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('ntp4', function() {
   'use strict';
 
   var localStrings = new LocalStrings;
 
   var APP_LAUNCH = {
@@ skipping 385 matching lines @@
     /**
      * Creates an app DOM element and places it at the last position on the
      * page.
      * @param {Object} appData The data object that describes the app.
      * @param {?boolean} animate If true, the app tile plays an animation.
      */
     appendApp: function(appData, animate) {
       this.appendTile(new App(appData), animate);
     },
 
+    /** @inheritdoc */
+    doDragOver: function(e) {
+      var tile = ntp4.getCurrentlyDraggingTile();
+      if (!tile.querySelector('.app')) {
+        e.preventDefault();
+        e.dataTransfer.dropEffect = 'copy';
+      } else {
+        TilePage.prototype.doDragOver.call(this, e);
+      }
+    },
+
     /** @inheritDoc */
     shouldAcceptDrag: function(e) {
       return ntp4.getCurrentlyDraggingTile() ||
           (e.dataTransfer && e.dataTransfer.types.indexOf('url') != -1);
     },
 
     /** @inheritDoc */
     addDragData: function(dataTransfer, index) {
       var currentlyDraggingTile = ntp4.getCurrentlyDraggingTile();
       if (currentlyDraggingTile) {
         var tileContents = currentlyDraggingTile.firstChild;
         if (tileContents.classList.contains('app')) {
           this.tileGrid_.insertBefore(
               currentlyDraggingTile,
               this.tileElements_[index]);
           this.tileMoved(currentlyDraggingTile);
-        } else if (tileContents.classList.contains('most-visited')) {
+        } else if (currentlyDraggingTile.querySelector('.most-visited')) {
           this.generateAppForLink(tileContents.data);
         }
       } else {
         this.addOutsideData_(dataTransfer, index);
       }
     },
 
     /**
      * Adds drag data that has been dropped from a source that is not a tile.
      * @param {Object} dataTransfer The data transfer object that holds drop
@@ skipping 33 matching lines @@
 
     /**
      * Creates a new crx-less app manifest and installs it.
      * @param {Object} data The data object describing the link. Must have |url|
      *     and |title| members.
      * TODO(estade): pass along an index.
      */
     generateAppForLink: function(data) {
       assert(data.url != undefined);
       assert(data.title != undefined);
-      chrome.send('generateAppForLink', [data.url, data.title]);
+      var pageIndex = ntp4.getAppsPageIndex(this);
+      chrome.send('generateAppForLink', [data.url, data.title, pageIndex]);
     },
 
     /** @inheritDoc */
     tileMoved: function(draggedTile) {
       if (!(draggedTile.firstChild instanceof App))
         return;
 
       var pageIndex = ntp4.getAppsPageIndex(this);
       chrome.send('setPageIndex', [draggedTile.firstChild.appId, pageIndex]);
 
@@ skipping 12 matching lines @@
     var store = document.querySelector('.webstore');
     if (store)
       store.setAppsPromoData(data);
   };
 
   return {
     APP_LAUNCH: APP_LAUNCH,
     AppsPage: AppsPage,
   };
 });