Update chrome.metricsPrivate externs and make closure fixes

ui/file_manager/image_loader/image_loader_client.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.
 
 /**
  * Client used to connect to the remote ImageLoader extension. Client class runs
  * in the extension, where the client.js is included (eg. Files.app).
  * It sends remote requests using IPC to the ImageLoader class and forwards
  * its responses.
  *
@@ skipping 42 matching lines @@
 };
 
 /**
  * Records binary metrics. Counts for true and false are stored as a histogram.
  * @param {string} name Histogram's name.
  * @param {boolean} value True or false.
  */
 ImageLoaderClient.recordBinary = function(name, value) {
   chrome.metricsPrivate.recordValue(
       { metricName: 'ImageLoader.Client.' + name,
-        type: 'histogram-linear',
+        type: chrome.metricsPrivate.MetricTypeType.HISTOGRAM_LINEAR,
         min: 1,  // According to histogram.h, this should be 1 for enums.
         max: 2,  // Maximum should be exclusive.
         buckets: 3 },  // Number of buckets: 0, 1 and overflowing 2.
       value ? 1 : 0);
 };
 
 /**
  * Records percent metrics, stored as a histogram.
  * @param {string} name Histogram's name.
  * @param {number} value Value (0..100).
@@ skipping 200 matching lines @@
       onError();
       return;
     }
     image.src = result.data;
     onSuccess();
   };
 
   return ImageLoaderClient.getInstance().load(
       url, callback, options, opt_isValid);
 };