Add session id to grant button clicked proto

This is needed to track the link to settings to actions done in the
settings screen.

Test: statsd_testdrive
Fixes: 149053996
Change-Id: I1c2260ad795b3d1c34bba753cd3d44a75766b7e6

cmds/statsd/src/atoms.proto

@@ -7509,6 +7509,9 @@ message GrantPermissionsActivityButtonActions {
 
     // Button clicked by user - same as bit flags in buttons_presented with only single bit set
     optional int32 button_clicked = 5;
+
+    // id which identifies single session of user interacting with permission controller
+    optional int64 session_id = 6;
 }
 
 /**