Adding location events to the histogram

tools/metrics/histograms/histograms.xml

 <!--
 Copyright 2013 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 used to generate a comprehensive list of Chrome histograms along
 with a detailed description for each histogram.
 
@@ skipping 11166 matching lines @@
 
 <enum name="GoogleNowEvent" type="int">
   <summary>
     Events in Google Now component extension. See var DiagnosticEvent.
   </summary>
   <int value="0" label="REQUEST_FOR_CARDS_TOTAL"/>
   <int value="1" label="REQUEST_FOR_CARDS_SUCCESS"/>
   <int value="2" label="CARDS_PARSE_SUCCESS"/>
   <int value="3" label="DISMISS_REQUEST_TOTAL"/>
   <int value="4" label="DISMISS_REQUEST_SUCCESS"/>
+  <int value="5" label="LOCATION_REQUEST"/>
+  <int value="6" label="LOCATION_EVENT"/>
 </enum>
 
 <enum name="HttpAuthCount" type="int">
   <int value="0" label="Basic Start"/>
   <int value="1" label="Basic Reject"/>
   <int value="2" label="Digest Start"/>
   <int value="3" label="Digest Reject"/>
   <int value="4" label="NTLM Start"/>
   <int value="5" label="NTLM Reject"/>
   <int value="6" label="Negotiate Start"/>
@@ skipping 4051 matching lines @@
 <fieldtrial name="SSLResumption">
   <group name="Resume_Handshake" label="Session Resumption"/>
   <group name="Full_Handshake" label="Full"/>
   <affected-histogram name="Net.SSL_Connection_Latency"/>
   <affected-histogram name="Net.SSL_Connection_Latency_Google"/>
 </fieldtrial>
 
 </fieldtrials>
 
 </histogram-configuration>