[cros] OOBE avatar picker fixes and polishing.

chrome/browser/resources/chromeos/user_images_grid.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('options', function() {
   /** @const */ var ArrayDataModel = cr.ui.ArrayDataModel;
   /** @const */ var Grid = cr.ui.Grid;
   /** @const */ var GridItem = cr.ui.GridItem;
   /** @const */ var GridSelectionController = cr.ui.GridSelectionController;
   /** @const */ var ListSingleSelectionModel = cr.ui.ListSingleSelectionModel;
@@ skipping 170 matching lines @@
      * Updates the preview image, if present.
      * @private
      */
     updatePreview_: function() {
       var url = this.selectedItemUrl;
       if (url && this.previewImage_)
         this.previewImage_.src = url;
     },
 
     /**
-     * @param {boolean} present Whether a camera is present or not.
+     * Whether a camera is present or not.
+     * @type {boolean}
      */
     get cameraPresent() {
       return this.cameraPresent_;
     },
     set cameraPresent(value) {
       this.cameraPresent_ = value;
       if (this.cameraLive)
         this.cameraImage = null;
     },
 
     /**
+     * Whether camera is actually streaming video. May be |false| even when
+     * camera is present and shown but still initializing.
+     * @type {boolean}
+     */
+    get cameraOnline() {
+      return this.previewElement.classList.contains('online');
+    },
+
+    /**
      * Start camera presence check.
      * @param {boolean} autoplay Whether to start capture immediately.
      * @param {boolean} preselect Whether to select camera automatically.
      */
     checkCameraPresence: function(autoplay, preselect) {
       this.previewElement.classList.remove('online');
       if (!this.cameraVideo_)
         return;
       navigator.webkitGetUserMedia(
           {video: true},
@@ skipping 219 matching lines @@
     },
     set flipPhoto(value) {
       this.flipPhoto_ = value;
       this.previewElement.classList[value ? 'add' : 'remove']('flip-x');
     },
 
     /**
      * Performs photo capture from the live camera stream.
      * @param {function=} opt_callback Callback that receives taken photo as
      *     data URL.
+     * @return {boolean} Whether photo capture was successful.
      */
     takePhoto: function(opt_callback) {
+      if (!this.cameraOnline)
+        return false;
       var canvas = document.createElement('canvas');
       canvas.width = CAPTURE_SIZE.width;
       canvas.height = CAPTURE_SIZE.height;
       this.captureFrame_(
           this.cameraVideo_, canvas.getContext('2d'), CAPTURE_SIZE);
       var photoURL = canvas.toDataURL('image/png');
       if (opt_callback && typeof opt_callback == 'function')
         opt_callback(photoURL);
       // Wait until image is loaded before displaying it.
       var self = this;
       var previewImg = new Image();
       previewImg.addEventListener('load', function(e) {
         self.cameraImage = this.src;
       });
       previewImg.src = photoURL;
+      return true;
     },
 
     /**
      * Performs video capture from the live camera stream.
      * @param {function=} opt_callback Callback that receives taken video as
      *     data URL of a vertically stacked PNG sprite.
      */
     takeVideo: function(opt_callback) {
       var canvas = document.createElement('canvas');
       canvas.width = CAPTURE_SIZE.width;
@@ skipping 182 matching lines @@
   UserImagesGrid.ButtonImages = {
     TAKE_PHOTO: 'chrome://theme/IDR_BUTTON_USER_IMAGE_TAKE_PHOTO',
     CHOOSE_FILE: 'chrome://theme/IDR_BUTTON_USER_IMAGE_CHOOSE_FILE',
     PROFILE_PICTURE: 'chrome://theme/IDR_PROFILE_PICTURE_LOADING'
   };
 
   return {
     UserImagesGrid: UserImagesGrid
   };
 });