D2MIOS: Add plumbing to query verified number and send SMS from growth server.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index eef0a376034b7a9d51553b265a49c94b159950ff..fee54417c06abfce3e9c5ef2ffa9783ea9e1fa15 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -10071,6 +10071,23 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="DesktopIOSPromotion.OAuthTokenCompletion"
+    enum="BooleanSuccess">
+  <owner>justincohen@chromium.org</owner>
+  <summary>
+    Whether getting the OAuth token was successful for a desktop to ios
+    promotion query.
+  </summary>
+</histogram>
+
+<histogram name="DesktopIOSPromotion.OAuthTokenResponseCode" units="code">

[rkaplow, 2017/01/30 16:36:31]

you need to put the correct enum here

[justincohen, 2017/01/30 18:30:20]

I see a bunch of other histogram's with units="code" and no corresponding enum. 
Perhaps I should switch "code" -> "CombinedHttpResponseAndNetErrorCode" ?

[justincohen, 2017/01/30 23:56:53]

Done.

+  <owner>justincohen@chromium.org</owner>
+  <summary>
+    HTTP Response code returned by the server when trying to fetch the OAuth
+    token for a desktop ios promotion query.
+  </summary>
+</histogram>
+
 <histogram name="DevTools.ActionTaken" enum="DevToolsAction">
   <owner>sergeyv@chromium.org</owner>
   <owner>vsevik@chromium.org</owner>