add UMA metrics for voice interaction entries.

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 16825 matching lines @@
 <action name="ViewSource">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
 </action>
 
 <action name="VirtualKeyboardLoaded">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
 </action>
 
+<action name="VoiceInteraction.Entry.AppListButtonLongPress">

[Ilya Sherman, 2017/05/24 05:47:59]

Optional nit: I'd choose "Started" or "Launched" or even "Entered" over "Entry".

[Daniel Erat, 2017/05/24 13:07:55]

agreed. "entry" is ambiguous about whether it refers to entering something vs.
e.g. an entry in a list of items.

[Muyuan, 2017/05/24 17:48:57]

Done.

[Muyuan, 2017/05/24 17:48:57]

Done.

+  <owner>muyuanli@chromium.org</owner>
+  <description>
+    User launches voice interaction session through long pressing app list

[Ilya Sherman, 2017/05/24 05:47:59]

nit: s/launches/launched (and ditto throughout)

[Muyuan, 2017/05/24 17:48:57]

Done.

+    button.
+  </description>
+</action>
+
+<action name="VoiceInteraction.Entry.Search_A">
+  <owner>muyuanli@chromium.org</owner>
+  <description>
+    User launches voice interaction session through Search + A.
+  </description>
+</action>
+
+<action name="VoiceInteraction.Entry.Search_Space">
+  <owner>muyuanli@chromium.org</owner>
+  <description>
+    User launches voice interaction session through Search + Space.
+  </description>
+</action>
+
+<action name="VoiceInteraction.MetaLayerEntry.Search_Shift_A">
+  <owner>muyuanli@chromium.org</owner>
+  <description>
+    User launches meta layer through Search + Shift + A.

[Daniel Erat, 2017/05/24 13:07:55]

"metalayer" here too if that's what's typically used to refer to it

[Muyuan, 2017/05/24 17:48:57]

Done.

+  </description>
+</action>
+
 <action name="WP_EditImage">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
 </action>
 
 <action name="WP_Gallery">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
 </action>
 
@@ skipping 446 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>