Don't rely on transitively included headers

One must explicitly include what it need.
time.h for clock_gettime

Bug: 37629934
Test: build
Merged-In: I992eac637f373b204aa161b0b26f5563e952c27e
Change-Id: I992eac637f373b204aa161b0b26f5563e952c27e
1 file changed