MD Downloads: reduce the size of the ellided, displayed download URL

chrome/browser/resources/md_downloads/item.js

 // Copyright 2015 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('downloads', function() {
   var Item = Polymer({
     is: 'downloads-item',
 
     properties: {
       data: {
@@ skipping 60 matching lines @@
       // TODO(dbeam): this gets called way more when I observe data.by_ext_id
       // and data.by_ext_name directly. Why?
       'observeControlledBy_(controlledBy_)',
       'observeIsDangerous_(isDangerous_, data)',
     ],
 
     ready: function() {
       this.content = this.$.content;
     },
 
+    /**
+     * @param {string} url
+     * @return {string} A reasonably long URL.
+     * @private
+     */
+    chopUrl_: function(url) {
+      return url.slice(0, 300);
+    },
+
     /** @private */
     computeClass_: function() {
       var classes = [];
 
       if (this.isActive_)
         classes.push('is-active');
 
       if (this.isDangerous_)
         classes.push('dangerous');
 
@@ skipping 223 matching lines @@
     },
 
     /** @private */
     onShowTap_: function() {
       downloads.ActionService.getInstance().show(this.data.id);
     },
   });
 
   return {Item: Item};
 });