Merge "Nullability check for wchar module." am: 182cebf612 am: bee044207b am: 1d23754ce7 am: 224d6027d9

Original change: https://android-review.googlesource.com/c/platform/bionic/+/2519858

Change-Id: I4243a2e05f7004324f92dbf46b926e54f949a5a2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>