Match debuggerd timestamps in SIGQUIT dumps.

An OEM asked for sub-second granularity for debuggerd and ART.

While I'm here, add the UTC offset that's in the debuggerd timestamps
but not in the ART ones.

Bug: https://issuetracker.google.com/161860597
Test: kill -QUIT zygote
Change-Id: I6b834689bd71bf7f4b2a74cc0045f60d1c6af020
1 file changed