Enable SPLIT_SHADE_SUBPIXEL_OPTIMIZATION for Droidfood

Enable SPLIT_SHADE_SUBPIXEL_OPTIMIZATION flag for droidfooders.

Cherry picked If15b4f31ed4600af3533db544e7fec4acabe49c6 to master due to b/286408867.

Code was merged via `-s ours` and is missing even though the sha exists on the target branch. Cherry pick is required to bring in the code.

Manually remove the "Merged in" directive to allow for downstream propagation.

Test: go/latency-compare-23516796
Bug: 277201412
Fixes: 280771268
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:345efc934f0cee2ca4ab53b7563beb461a555ac8)
Change-Id: I4dca16517a8bcbe7f3429c9082d26e448d0ac227