Implementing sign-in promo histograms for settings

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 a4dd09acd35abca4d5afc02a37f004c0b310ab7a..25162f94a3d46a95a581c93e9997409f599800ae 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -32767,6 +32767,26 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="MobileSignInPromo.SettingsManager.ImpressionsTilDismiss"
+    units="impressions">
+  <owner>jlebel@chromium.org</owner>
+  <summary>
+    Counts how many times the signin promo is implicitly dismissed (by closing

[rkaplow, 2017/06/28 15:20:16]

if these are only iOS, ca you mention in the summary.

[jlebel, 2017/06/29 00:00:53]

Done.

+    the settings view) per impression.
+  </summary>
+</histogram>
+
+<histogram name="MobileSignInPromo.SettingsManager.ImpressionsTilSigninButtons"
+    units="impressions">
+  <owner>jlebel@chromium.org</owner>
+  <summary>
+    Counts how many times one of the &quot;sign in&quot; buttons (any of the
+    signed-out &quot;Sign in to Chrome&quot; button, the &quot;Continue as
+    |name|&quot; button, or the &quot;Not |email|?&quot; button) is clicked per
+    impression.
+  </summary>
+</histogram>
+
 <histogram name="MobileStartup.IntentToCreationTime" units="ms">
   <owner>twellington@chromium.org</owner>
   <summary>