Reapply "Set FLAG_DECLARATION_FILES value"

Have the release config map specify where to find build flag
declarations, rather than having the logic in the build system.

This reverts commit b737448b4441acc546b333bf251246ab0ffd4bb6.

Bug: b/302593603
Test: manual
Change-Id: I5e23a5719ad54019dc1e9daa20a1e33fc64af034
1 file changed
tree: fc2f3dc2665c7e2fa9b6ed61a37b6e0c446cac10
  1. aconfig/
  2. build_config/
  3. build_flags.bzl
  4. OWNERS
  5. release_config_map.mk