Files.app: Add metrics of RAW file loading time.

ui/file_manager/image_loader/request.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.
 
 /**
  * @typedef {{
  *   cache: (boolean|undefined),
  *   priority: (number|undefined),
  *   taskId: number,
  *   timestamp: (number|undefined),
@@ skipping 219 matching lines @@
   // Download data urls directly since they are not supported by XmlHttpRequest.
   var dataUrlMatches = this.request_.url.match(/^data:([^,;]*)[,;]/);
   if (dataUrlMatches) {
     this.image_.src = this.request_.url;
     this.contentType_ = dataUrlMatches[1];
     return;
   }
 
   // Load RAW images by using Piex loader instead of XHR.
   if (FileType.getTypeForName(this.request_.url).type === 'raw') {
+    var startTime = new Date();

[Ben Kwa, 2015/04/10 15:57:31]

If you don't want to mess with raw Dates there's also
analytics.Tracker#startTiming which returns a timer object that you call #send
on when you want the timing to stop.  But what you have here also works fine.

     this.piexLoader_.load(this.request_.url).then(function(data) {
+      this.recordRawLoadingTime_(this.request_.url, startTime, new Date());
       var blob = new Blob([data.thumbnail], {type: 'image/jpeg'});
       var url = URL.createObjectURL(blob);
       this.image_.src = url;
       this.request_.orientation = data.orientation;
       this.request_.colorSpace = data.colorSpace;
     }.bind(this), function(error) {
       console.error('PiexLoaderError: ', error);
       onFailure();
     });
     return;
   }
 
   // Fetch the image via authorized XHR and parse it.
   var parseImage = function(contentType, blob) {
     if (contentType)
       this.contentType_ = contentType;
     this.image_.src = URL.createObjectURL(blob);
   }.bind(this);
 
   // Request raw data via XHR.
   this.xhr_.load(this.request_.url, parseImage, onFailure);
 };
 
 /**
+ * Records loading time of RAW files.
+ * @param {string} url
+ * @param {!Date} startTime
+ * @param {!Date} endTime
+ */
+Request.prototype.recordRawLoadingTime_ = function(url, startTime, endTime) {
+  var type = FileType.getTypeForName(url);
+  var metricVariable;
+  switch (type.subtype) {
+    case 'ARW':
+      metricVariable = metrics.timing.Variables.RAW_LOAD_ARW;
+      break;
+    case 'CR2':
+      metricVariable = metrics.timing.Variables.RAW_LOAD_CR2;
+      break;
+    case 'DNG':
+      metricVariable = metrics.timing.Variables.RAW_LOAD_DNG;
+      break;
+    case 'NEF':
+      metricVariable = metrics.timing.Variables.RAW_LOAD_NEF;
+      break;
+    case 'NRW':
+      metricVariable = metrics.timing.Variables.RAW_LOAD_NRW;
+      break;
+    case 'ORF':
+      metricVariable = metrics.timing.Variables.RAW_LOAD_ORF;
+      break;
+    case 'RAF':
+      metricVariable = metrics.timing.Variables.RAW_LOAD_RAF;
+      break;
+    case 'RW2':
+      metricVariable = metrics.timing.Variables.RAW_LOAD_RW2;
+      break;
+    default:
+      console.error('Invalid RAW type: ' + type.subtype + '.');
+      return;
+  }
+  metrics.getTracker().sendTiming(
+      metrics.Categories.RAW_IMAGE,
+      metricVariable,
+      endTime.getTime() - startTime.getTime());
+};
+
+/**
  * Creates a XmlHttpRequest wrapper with injected OAuth2 authentication headers.
  * @constructor
  */
 function AuthorizedXHR() {
   this.xhr_ = null;
   this.aborted_ = false;
 }
 
 /**
  * A map which is used to estimate content type from extension.
@@ skipping 252 matching lines @@
   this.image_.src = 'data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAA' +
       'ABAAEAAAICTAEAOw==';
 
   this.xhr_.onload = function() {};
   this.xhr_.abort();
 
   // Dispose memory allocated by Canvas.
   this.canvas_.width = 0;
   this.canvas_.height = 0;
 };