Add the 'content' column to see what text is used to detect a language

chrome/browser/resources/translate_internals/translate_internals.js

 // Copyright 2013 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.
 
 (function() {
   'use strict';
 
   cr.define('cr.translateInternals', function() {
 
+    var detectionLogs_ = null;
+
+    function detectionLogs() {
+      if (detectionLogs_ === null)
+        detectionLogs_ = [];
+      return detectionLogs_;
+    }
+
     /**
      * Initializes UI and sends a message to the browser for
      * initialization.
      */
     function initialize() {
       cr.ui.decorate('tabbox', cr.ui.TabBox);
       chrome.send('requestInfo');
+
+      var button = $('detection-logs-dump');
+      button.addEventListener('click', onDetectionLogsDump);
     }
 
     /**
      * Creates a new LI element with a button to dismiss the item.
      *
      * @param {string} text The lable of the LI element.
      * @param {Function} func Callback called when the button is clicked.
      */
     function createLIWithDismissingButton(text, func) {
       var span = document.createElement('span');
@@ skipping 177 matching lines @@
       return td;
     }
 
     /**
      * Handles the message of 'languageDetectionInfoAdded' from the
      * browser.
      *
      * @param {Object} detail The object which represents the logs.
      */
     function onLanguageDetectionInfoAdded(detail) {
+      cr.translateInternals.detectionLogs().push(detail);
+
       var tr = document.createElement('tr');
 
       var date = new Date(detail['time']);
       [
         createTD(formatDate(date), 'detection-logs-time'),
         createTD(detail['url'], 'detection-logs-url'),
         createTD(formatLanguageCode(detail['content_language']),
                  'detection-logs-content-language'),
         createTD(formatLanguageCode(detail['cld_language']),
                  'detection-logs-cld-language'),
         createTD(detail['is_cld_reliable'],
                  'detection-logs-is-cld-reliable'),
         createTD(formatLanguageCode(detail['language']),
                  'detection-logs-language'),
+        createTD(formatLanguageCode(detail['content']),
+                 'detection-logs-content'),
       ].forEach(function(td) {
         tr.appendChild(td);
       });
 
+      // TD (and TR) can't use the CSS property 'max-height', so DIV
+      // in the content is needed.
+      var contentTD = tr.querySelector('.detection-logs-content');
+      var div = document.createElement('div');
+      div.textContent = contentTD.textContent;
+      contentTD.textContent = '';
+      contentTD.appendChild(div);
+
       var tbody = $('detection-logs').getElementsByTagName('tbody')[0];
       tbody.appendChild(tr);
     }
 
     /**
      * Handles the message of 'translateErrorDetailsAdded' from the
      * browser.
      *
      * @param {Object} details The object which represents the logs.
      */
@@ skipping 32 matching lines @@
           break;
         case 'translateErrorDetailsAdded':
           cr.translateInternals.onTranslateErrorDetailsAdded(detail);
           break;
         default:
           console.error('Unknown message:', message);
           break;
       }
     }
 
+    /**
+     * The callback of button#detetion-logs-dump.
+     */
+    function onDetectionLogsDump() {
+      var data = JSON.stringify(cr.translateInternals.detectionLogs());
+      var blob = new Blob([data], {'type': 'text/json'});
+      var url = webkitURL.createObjectURL(blob);
+      var filename = 'translate_internals_detect_logs_dump.json';
+
+      var a = document.createElement('a');
+      a.setAttribute('href', url);
+      a.setAttribute('download', filename);
+
+      var event = document.createEvent('MouseEvent');
+      event.initMouseEvent('click', true, true, window, 0,
+                           0, 0, 0, 0, 0, 0, 0, 0, 0, null);
+      a.dispatchEvent(event);
+    }
+
     return {
+      detectionLogs: detectionLogs,
       initialize: initialize,
       messageHandler: messageHandler,
       onLanguageDetectionInfoAdded: onLanguageDetectionInfoAdded,
       onPrefsUpdated: onPrefsUpdated,
       onTranslateErrorDetailsAdded: onTranslateErrorDetailsAdded,
     };
   });
 
   /**
    * The entry point of the UI.
    */
   function main() {
     cr.doc.addEventListener('DOMContentLoaded',
                             cr.translateInternals.initialize);
   }
 
   main();
 })();