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

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



Change-Id: If14f9e876aee26b12a2cd9f27b0a3e993e552a59
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>