[filebrowser] Historgram for the file browser's open time.

chrome/browser/resources/file_manager/js/metrics.js

+// Copyright (c) 2011 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.
+
+/**
+ * @fileoverview Utility methods for accessing chrome.experimental.metrics API.
+ *
+ * To be included as a first script in main.html
+ */
+
+var metrics = {};
+
+metrics.intervals = {};
+
+metrics.startInterval = function(name) {
+  metrics.intervals[name] = Date.now();
+};
+
+metrics.startInterval('TotalLoad');
+metrics.startInterval('ScriptParse');
+
+metrics.convertName_ = function(name) {
+  // chrome.experimental.metrics will append extension ID after the last dot.
+  return 'FileBrowser.' + name + '.';
+};
+
+metrics.recordTime = function(name) {
+  if (name in metrics.intervals) {
+    var elapsed = Date.now() - metrics.intervals[name];
+    console.log(name + ': ' + elapsed + 'ms');

[SeRya, 2011/11/07 13:29:23]

I think we we shouldn't litter in the common log by default (at least without
strong reason). 

[Vladislav Kaznacheev, 2011/11/08 11:06:20]

I suggest keeping this for the time being because these numbers are actually
very useful while we are fighting for the startup performance. Once we are done
with that we shall clean the logging up.

On 2011/11/07 13:29:23, SeRya wrote:

+    chrome.experimental.metrics.recordTime(metrics.convertName_(name), elapsed);
+  } else {
+    console.error('Unknown interval: ' + name);
+  }
+};
+
+metrics.recordAction = function(name) {
+  chrome.experimental.metrics.recordUserAction(metrics.convertName_(name));
+};