Add Rappor reporting for grant/deny/cancel/ignore of Mediastream permissions

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 b96ffab5a565ef2d38b0afd6f8f4fe8202688ee8..e2d230342c923ad3438650a4146527fc3163de8b 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -17578,6 +17578,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Media.DevicePermissionActions" enum="DevicePermissionActions">
+  <obsolete>
+    Removed 10/2015 in favor of Permissions.Action.
+  </obsolete>
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <summary>
     Measures the actions taken in the media infobar, which prompts the users for
@@ -31085,6 +31088,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Permissions.Action" enum="PermissionAction">
+  <owner>miguelg@chromium.org</owner>

[mlamouri (slow - plz ping), 2015/10/20 11:00:41]

nit: add me, please :)

[tsergeant, 2015/10/21 02:44:49]

Done.

+  <summary>
+    Tracks whether a permission was granted, rejected, etc. The suffix of the
+    histogram indicates which particular permission.
+  </summary>
+</histogram>
+
 <histogram name="Permissions.Requested.CrossOrigin" enum="PermissionStatus">
   <owner>keenanb@google.com</owner>
   <owner>jww@chromium.org</owner>
@@ -78852,9 +78863,12 @@ To add a new entry, add it with any value and run test to compute valid value.
   <suffix name="Geolocation" label="Geolocation permission actions"/>
   <suffix name="ProtectedMedia" label="Protected media permission actions"/>
   <suffix name="DurableStorage" label="Durable Storage permission actions"/>
+  <suffix name="AudioCapture" label="Microphone permission actions"/>
+  <suffix name="VideoCapture" label="Camera permission actions"/>
   <affected-histogram name="ContentSettings.PermissionActions"/>
   <affected-histogram name="ContentSettings.PermissionActionsInsecureOrigin"/>
   <affected-histogram name="ContentSettings.PermissionActionsSecureOrigin"/>
+  <affected-histogram name="Permissions.Action"/>
   <affected-histogram name="Permissions.Requested.CrossOrigin"/>
 </histogram_suffixes>