Merge from Widevine repo of http://go/wvgerrit/24727
This separates out the logging of decrypt calls from all other calls.
This is useful because we sometimes want to trace all the calls in a
license request, but we don't want logging of decrypt calls which
would slow down playback.
b/37353534
b/35141278
Change-Id: I3f172c02778d86e66d0e1f90344a34c4d3b15a9e