Add field trial and flag to mark HTTP as non-secure.

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 171 matching lines @@
 <action name="AboutFlags_instant-autocomplete-immediately">
   <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="AboutFlags_instant-type">
   <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="AboutFlags_mark-http-as-non-secure">
+  <owner>palmer@chromium.org</owner>
+  <owner>felt@chromium.org</owner>
+  <description>
+    This flag lets users opt into or out of marking HTTP as Dubious or as
+    Non-Secure. The counter is emitted once per startup when the flag is active.

[Mark P, 2015/01/08 00:06:54]

nit: ^counter^action

+  </description>
+</action>
+
 <action name="AboutFlags_match-preview">
   <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="AboutFlags_my-special-feature">
   <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 11663 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>