Ensure Default Dialer is on power exemption after receiving missed call notification

If the default dialer is handling the missed call notification, check to make
sure it has been temporarily exempted from power restrictions.

Bug: 160724034
Test: atest CtsTelecomTestCases:MissedCallTest
Change-Id: I5d3c0774e68cfee932da922f94aec9acd49e48e3
1 file changed