Add UMA for Quick View (file type and volume type).

ui/file_manager/file_manager/foreground/js/quick_view_uma.js

Index: ui/file_manager/file_manager/foreground/js/quick_view_uma.js
diff --git a/ui/file_manager/file_manager/foreground/js/quick_view_uma.js b/ui/file_manager/file_manager/foreground/js/quick_view_uma.js
new file mode 100644
index 0000000000000000000000000000000000000000..7f43d93e1597797d5ef898f7657dd09983461d26
--- /dev/null
+++ b/ui/file_manager/file_manager/foreground/js/quick_view_uma.js
@@ -0,0 +1,64 @@
+// Copyright 2016 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.
+
+/**
+ * UMA exporter for Quick View.
+ *
+ * @param {!VolumeManagerWrapper} volumeManager
+ *
+ * @constructor
+ */
+function QuickViewUma(volumeManager) {
+
+  /**
+   * @type {!VolumeManagerWrapper}
+   * @private
+   */
+  this.volumeManager_ = volumeManager;
+}
+
+/**
+ * Keep the order of this in sync with FileManagerVolumeType in
+ * tools/metrics/histograms/histograms.xml.
+ *
+ * @type {!Array<VolumeManagerCommon.VolumeType>}
+ * @const
+ */
+QuickViewUma.VolumeType = [
+  VolumeManagerCommon.VolumeType.DRIVE,
+  VolumeManagerCommon.VolumeType.DOWNLOADS,
+  VolumeManagerCommon.VolumeType.REMOVABLE,
+  VolumeManagerCommon.VolumeType.ARCHIVE,
+  VolumeManagerCommon.VolumeType.PROVIDED,
+  VolumeManagerCommon.VolumeType.MTP,
+];
+
+/**
+ * Exports UMA based on the entry shown in Quick View.
+ *
+ * @param {!FileEntry} entry
+ */
+QuickViewUma.prototype.onEntryChanged = function(entry) {
+  var extension = FileType.getExtension(entry).toLowerCase();
+  if (FileTasks.UMA_INDEX_KNOWN_EXTENSIONS.indexOf(extension) < 0) {
+    extension = 'other';
+  }
+  metrics.recordEnum(
+      'QuickView.FileType', extension, FileTasks.UMA_INDEX_KNOWN_EXTENSIONS);
+};
+
+/**
+ * Exports UMA based on the entry selected when Quick View is opened.
+ *
+ * @param {!FileEntry} entry
+ */
+QuickViewUma.prototype.onOpened = function(entry) {
+  var volumeType = this.volumeManager_.getVolumeInfo(entry).volumeType;
+  if (QuickViewUma.VolumeType.includes(volumeType)) {
+    metrics.recordEnum(
+        'QuickView.VolumeType', volumeType, QuickViewUma.VolumeType);
+  } else {
+    console.error('Unknown volume type: ' + volumeType);
+  }
+};