Disable VK overscroll for login/out-of-box.

chrome/browser/resources/login/user_pod_row.js

 // Copyright 2014 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.
 
 /**
  * @fileoverview User pod row implementation.
  */
 
 cr.define('login', function() {
   /**
@@ skipping 29 matching lines @@
    * Variables used for pod placement processing. Width and height should be
    * synced with computed CSS sizes of pods.
    */
   var POD_WIDTH = 180;
   var PUBLIC_EXPANDED_WIDTH = 420;
   var CROS_POD_HEIGHT = 213;
   var DESKTOP_POD_HEIGHT = 216;
   var POD_ROW_PADDING = 10;
 
   /**
+   * Minimal padding between user pod and virtual keyboard.
+   * @type {number}
+   * @const
+   */
+  var USER_POD_KEYBOARD_MIN_PADDING = 20;
+
+  /**
    * Whether to preselect the first pod automatically on login screen.
    * @type {boolean}
    * @const
    */
   var PRESELECT_FIRST_POD = true;
 
   /**
    * Maximum time for which the pod row remains hidden until all user images
    * have been loaded.
    * @type {number}
@@ skipping 1493 matching lines @@
      * @param {boolean} animated Whether to use init animation.
      */
     loadPods: function(users, animated) {
       this.users_ = users;
       this.userAddIsAnimated_ = animated;
 
       this.rebuildPods();
     },
 
     /**
+     * Scrolls focused user pod into view.
+     */
+    scrollFocusedPodIntoView: function() {
+      var pod = this.focusedPod_;
+      if (!pod)
+        return;
+
+      // First check whether focused pod is already fully visible.
+      var visibleArea = $('scroll-container');
+      var scrollTop = visibleArea.scrollTop;
+      var clientHeight = visibleArea.clientHeight;
+      var podTop = $('oobe').offsetTop + pod.offsetTop;
+      var padding = USER_POD_KEYBOARD_MIN_PADDING;
+      if (podTop + pod.height + padding <= scrollTop + clientHeight &&
+          podTop - padding >= scrollTop) {
+        return;
+      }
+
+      // Scroll so that user pod is as centered as possible.
+      visibleArea.scrollTop = podTop - (clientHeight - pod.offsetHeight) / 2;
+    },
+
+    /**
      * Rebuilds pod row using users_ and apps_ that were previously set or
      * updated.
      */
     rebuildPods: function() {
       var emptyPodRow = this.pods.length == 0;
 
       // Clear existing pods.
       this.innerHTML = '';
       this.focusedPod_ = undefined;
       this.activatedPod_ = undefined;
@@ skipping 154 matching lines @@
                                         BUBBLE_PADDING);
     },
 
     /**
      * Called when window was resized.
      */
     onWindowResize: function() {
       var layout = this.calculateLayout_();
       if (layout.columns != this.columns || layout.rows != this.rows)
         this.placePods_();
+
+      if (Oobe.getInstance().virtualKeyboardShown)
+        this.scrollFocusedPodIntoView();
     },
 
     /**
      * Returns width of podrow having |columns| number of columns.
      * @private
      */
     columnsToWidth_: function(columns) {
       var margin = MARGIN_BY_COLUMNS[columns];
       return 2 * POD_ROW_PADDING + columns *
           this.userPodWidth_ + (columns - 1) * margin;
@@ skipping 75 matching lines @@
 
     /**
      * Number of columns.
      * @type {?number}
      */
     set columns(columns) {
       // Cannot use 'columns' here.
       this.setAttribute('ncolumns', columns);
     },
     get columns() {
-      return this.getAttribute('ncolumns');
+      return parseInt(this.getAttribute('ncolumns'));
     },
 
     /**
      * Number of rows.
      * @type {?number}
      */
     set rows(rows) {
       // Cannot use 'rows' here.
       this.setAttribute('nrows', rows);
     },
     get rows() {
-      return this.getAttribute('nrows');
+      return parseInt(this.getAttribute('nrows'));
     },
 
     /**
      * Whether the pod is currently focused.
      * @param {UserPod} pod Pod to check for focus.
      * @return {boolean} Pod focus status.
      */
     isFocused: function(pod) {
       return this.focusedPod_ == pod;
     },
@@ skipping 45 matching lines @@
       this.focusedPod_ = podToFocus;
       if (podToFocus) {
         podToFocus.classList.remove('faded');
         podToFocus.classList.add('focused');
         podToFocus.reset(true);  // Reset and give focus.
         // focusPod() automatically loads wallpaper
         if (!podToFocus.user.isApp)
           chrome.send('focusPod', [podToFocus.user.username]);
         this.firstShown_ = false;
         this.lastFocusedPod_ = podToFocus;
+
+        if (Oobe.getInstance().virtualKeyboardShown)
+          this.scrollFocusedPodIntoView();
       }
       this.insideFocusPod_ = false;
       this.keyboardActivated_ = false;
     },
 
     /**
      * Focuses a given user pod by index or clear focus when given null.
      * @param {int=} podToFocus index of User pod to focus.
      * @param {boolean=} opt_force If true, forces focus update even when
      *     podToFocus is already focused.
@@ skipping 318 matching lines @@
       if (this.podsWithPendingImages_.length == 0) {
         this.classList.remove('images-loading');
       }
     }
   };
 
   return {
     PodRow: PodRow
   };
 });