Revert of Revert "Typecheck JS files for chrome://extensions"

ui/webui/resources/js/cr/ui/array_data_model.js

Index: ui/webui/resources/js/cr/ui/array_data_model.js
diff --git a/ui/webui/resources/js/cr/ui/array_data_model.js b/ui/webui/resources/js/cr/ui/array_data_model.js
index f8d649ccb27a9dadcda113122c0c9a2605cd648a..9254dc378fbcabb7f46ab2a4ea134c39cc3945b6 100644
--- a/ui/webui/resources/js/cr/ui/array_data_model.js
+++ b/ui/webui/resources/js/cr/ui/array_data_model.js
@@ -5,6 +5,14 @@
 /**
  * @fileoverview This is a data model representin
  */
+
+// The include directives are put into Javascript-style comments to prevent
+// parsing errors in non-flattened mode. The flattener still sees them.
+// Note that this makes the flattener to comment out the first line of the
+// included file but that's all right since any javascript file should start
+// with a copyright comment anyway.
+
+//<include src="../../assert.js">
 
 cr.define('cr.ui', function() {
   /** @const */ var EventTarget = cr.EventTarget;
@@ -14,7 +22,7 @@
    * initial indexes of elements for each position in sorted array.
    * @param {!Array} array The underlying array.
    * @constructor
-   * @extends {EventTarget}
+   * @extends {cr.EventTarget}
    */
   function ArrayDataModel(array) {
     this.array_ = array;
@@ -62,7 +70,8 @@
     /**
      * Sets compare function for given field.
      * @param {string} field The field to set compare function.
-     * @param {function(*, *): number} Compare function to set for given field.
+     * @param {function(*, *): number} compareFunction Compare function to set
+     *     for given field.
      */
     setCompareFunction: function(field, compareFunction) {
       if (!this.compareFunctions_) {
@@ -127,7 +136,7 @@
      * the whole change.
      * @param {number} index The index of the item to update.
      * @param {number} deleteCount The number of items to remove.
-     * @param {...*} The items to add.
+     * @param {...*} var_args The items to add.
      * @return {!Array} An array with the removed items.
      */
     splice: function(index, deleteCount, var_args) {
@@ -202,7 +211,7 @@
      *
      * This dispatches a splice event.
      *
-     * @param {...*} The items to append.
+     * @param {...*} var_args The items to append.
      * @return {number} The new length of the model.
      */
     push: function(var_args) {
@@ -249,11 +258,9 @@
      * @param {Array.<number>} indexes The index list of items to update.
      */
     updateIndexes: function(indexes) {
-      var isIndexesValid = indexes.every(function(index) {
-        return 0 <= index && index < this.length;
+      indexes.forEach(function(index) {
+        assert(index >= 0 && index < this.length, 'Invalid index');
       }, this);
-      if (!isIndexesValid)
-        throw Error('Invalid index, ' + indexes[i]);
 
       for (var i = 0; i < indexes.length; i++) {
         var e = new Event('change');
@@ -276,8 +283,8 @@
 
     /**
      * Creates sort status with given field and direction.
-     * @param {string} field Sort field.
-     * @param {string} direction Sort direction.
+     * @param {?string} field Sort field.
+     * @param {?string} direction Sort direction.
      * @return {!Object} Created sort status.
      */
     createSortStatus: function(field, direction) {
@@ -382,7 +389,7 @@
      * Returns the function set as sortFunction for given field
      * or default compare function
      * @param {string} field Sort field.
-     * @param {function(*, *): number} Compare function.
+     * @return {function(*, *): number} Compare function.
      * @private
      */
     createCompareFunction_: function(field) {
@@ -396,14 +403,12 @@
           return defaultValuesCompareFunction.call(null, a[field], b[field]);
         }
       }
-      return compareFunction;
     },
 
     /**
      * Creates compare function for given field and direction.
      * @param {string} field Sort field.
      * @param {string} direction Sort direction.
-     * @param {function(*, *): number} Compare function.
      * @private
      */
     sortFunction_: function(field, direction) {