[Downloads UI] Implement search

tools/metrics/actions/actions.xml

 <!--
 Copyright 2014 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.
 -->
 
 <!--
 This file is a comprehensive list of Chrome user actions along with the owner
 and description for each user action.
 
@@ skipping 1111 matching lines @@
 
 <action name="Android.DownloadManager.OpenDrawer">
   <owner>dfalcantara@chromium.org</owner>
   <owner>twellington@chromium.org</owner>
   <owner>ianwen@chromium.org</owner>
   <description>
     User opened the navigation drawer in Chrome's download manager.
   </description>
 </action>
 
+<action name="Android.DownloadManager.Search">
+  <owner>dfalcantara@chromium.org</owner>
+  <owner>twellington@chromium.org</owner>
+  <description>User initiated a search of their downloads.</description>
+</action>
+
 <action name="Android.DownloadManager.SelectionEstablished">
   <owner>dfalcantara@chromium.org</owner>
   <owner>twellington@chromium.org</owner>
   <owner>ianwen@chromium.org</owner>
   <description>
     User established a long-press selection in Chrome's download manager.
   </description>
 </action>
 
 <action name="Android.DownloadManager.UndoDelete">
@@ skipping 15204 matching lines @@
 <action name="webapps.AddShortcut.Manifest">
   <owner>mlamouri@chromium.org</owner>
   <description>
     Shortcut added to the homescreen with a valid Manifest. This action will be
     recorded in addition to AppShortcut, AppShortcutApple and Bookmark actions
     to keep a trend of whether the webapp also add meta tags.
   </description>
 </action>
 
 </actions>