Merge "prune out empty bazel depsets" am: e136efdc am: 9e130a27

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/2404275



Change-Id: I65f5c077abfc6b45db515de1e0c995d8850ea5c9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>