aconfig: Cache flag values for c/c++ codegen am: 96506f43 am: 72d310b4

Original change: https://android-review.googlesource.com/c/platform/build/+/2822931



Change-Id: I0f18736ad3d460f48d2c5070aeac3f0f7a7b8266
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>