Use de-duped version on LoggingEvents now in android-common.

This CL now simply moves LatinIME to use the version of
LoggingEvents in android-common, rather than duplicating
the LoggingEvents class between VoiceSearch, Browser, and
LatinIME.

I also added in a TIMESTAMP to the START broadcast, so that
we would be able to evaluate if various events happened
after a user tried  Voice Input.

Change-Id: Ic88ff40fcedf707abc3c5eb2e68dfd0fcdef3701