Revert^2 "Disable -Wno-single-bit-bitfield-constant-conversion locally" am: c5cc7fc413

Original change: https://android-review.googlesource.com/c/platform/external/python/cpython2/+/3247806

Change-Id: I4eb6b8ad9f43fa0087e966eeb85aa8e8c21100d9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>