Add a build flag for storage areas

This adds a build flag for storage areas, a new feature that is
being developed on aosp/main. We need this build flag in order to
gate some new SELinux policies.
However, since it seems trunk_staging.scl is developed here on
internal main and our CLs in aosp/main are reporting merge conflicts,
we are submitting the build flag addition in this repo and will
pick it onto our aosp code.

Bug: 325129836
Test: m
Ignore-AOSP-First: merge conflict resolution
Change-Id: I2a45f8ff235a0e7fc905a90b210c7d75d4753351
Merged-In: I54cfa154f8a0a10a1e06763c3243b92f95c4b1cd
2 files changed
tree: dadc21e7a56e58f0fe5092e0e8484a08adb40d14
  1. aconfig/
  2. build_config/
  3. build_flags.scl
  4. OWNERS
  5. release_config_map.mk