Add ADPF setPreferPowerEfficiency mode

Adds a new viz feature (EnableAdpfEfficiencyMode) with three options:
* always_efficient, opts every ADPF session into
  setPreferPowerEfficiency for significant CPU energy savings
* never: current behaviour
* adaptive: currently a no-op, but will shift ADPF sessions between
  performance and efficiency modes

Bug: 464505581

Change-Id: I59b9d7bc514c1d1b529218da99c193f28e11dc92
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7205706
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Reviewed-by: Igor Kraskevich <kraskevich@google.com>
Commit-Queue: Richard Townsend <ritownsend@google.com>
Reviewed-by: Vladimir Levin <vmpstr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1554897}