Update prebuilt Clang to r383902b. am: e25ca94f0c am: 4314724279 am: 8ad3c957f0

Original change: https://googleplex-android-review.googlesource.com/c/platform/prebuilts/clang/host/darwin-x86/+/11834657

Change-Id: I611f38f25e88cf85d7697de9d3dfc6f10c16aacb