Avoid log spam in Files app

chrome/browser/resources/file_manager/js/metadata/metadata_cache.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.
 
 /**
  * MetadataCache is a map from url to an object containing properties.
  * Properties are divided by types, and all properties of one type are accessed
  * at once.
  * Some of the properties:
  * {
@@ skipping 825 matching lines @@
  * @param {Object} event The event.
  * @private
  */
 ContentProvider.prototype.onMessage_ = function(event) {
   var data = event.data;
 
   var methodName =
       'on' + data.verb.substr(0, 1).toUpperCase() + data.verb.substr(1) + '_';
 
   if (!(methodName in this)) {
-    console.log('Unknown message from metadata reader: ' + data.verb, data);
+    console.error('Unknown message from metadata reader: ' + data.verb, data);
     return;
   }
 
   this[methodName].apply(this, data.arguments);
 };
 
 /**
  * @return {boolean} Whether provider is ready.
  */
 ContentProvider.prototype.isInitialized = function() {
@@ skipping 64 matching lines @@
 
 /**
  * Handles the 'error' message from the worker.
  * @param {string} url File url.
  * @param {string} step Step failed.
  * @param {string} error Error description.
  * @param {Object?} metadata The metadata, if available.
  * @private
  */
 ContentProvider.prototype.onError_ = function(url, step, error, metadata) {
-  console.warn('metadata: ' + url + ': ' + step + ': ' + error);
+  if (localStorage.logMetadata)  // Avoid log spam by default.
+    console.warn('metadata: ' + url + ': ' + step + ': ' + error);
   metadata = metadata || {};
   // Prevent asking for thumbnail again.
   metadata.thumbnailURL = '';
   this.onResult_(url, metadata);
 };
 
 /**
  * Handles the 'log' message from the worker.
  * @param {Array.<*>} arglist Log arguments.
  * @private
  */
 ContentProvider.prototype.onLog_ = function(arglist) {
-  console.log.apply(console, ['metadata:'].concat(arglist));
+  if (localStorage.logMetadata)  // Avoid log spam by default.
+    console.log.apply(console, ['metadata:'].concat(arglist));
 };