Port pixelzoomer.js/css to ct-results-comparison.

Tools/GardeningServer/ui/ct-test-output.html

 <!--
 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.
 -->
 
  <polymer-element name="ct-test-output" attributes="type url">
     <template>
         <style>
             .result {
                 border: 1px solid gray;
+                line-height: 0;
             }
             iframe {
                 border: none;
                 width: 100%;
                 height: 400px;
             }
             img {
                 width: 100%;
             }
         </style>
@@ skipping 15 matching lines @@
     <script>
         Polymer({
             type: '',
             url: '',
             _kAudioType: results.kAudioType,
             _kImageType: results.kImageType,
             _kTextType: results.kTextType,
         });
     </script>
 </polymer-element>