Add metrics for emergency dialer

These include,
1. The entry point where user starts emergency dialer.
2. The duration that user stays at emergency dialer,
and if user takes further action before leaving this page.
3. The context when user has intention to make a phone call.

Bug: 111378820
Test: manual and check the result of
'adb logcat -b events | grep sysui_multi_action'

Change-Id: I3612008aadebbcbd0180ab6f238359984416920b
1 file changed