[codec][aac] Move BUILD.gn to this repo for easier merging

BUG: fxbug.dev/128466
Change-Id: I3d7e86afb2cc4fd9ed4fda87c9488cf59f9cb3f0
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/android/platform/external/aac/+/884255
Reviewed-by: David Fang <fangism@google.com>
1 file changed