time_in_state: track last update time per UID

This allows for optimizing reading this data by skipping UIDs that
have not been updated recently.

Bug: 138317993
Test: builds; libtimeinstate_test passes
Change-Id: Ic535d15d09dae274e47050f28a483c7d22b6ca04
Signed-off-by: Connor O'Brien <connoro@google.com>
1 file changed
tree: b64fa1d73e9db5ca884170ff8c2ebd627f0e0012
  1. Android.bp
  2. test/
  3. time_in_state.c