Merge "Revert "Use platform prebuilts from NDK r23 canary."" am: 3ff884f0a2

Original change: https://android-review.googlesource.com/c/platform/prebuilts/ndk/+/1658454

Change-Id: Idaf7f6a9a31b0ecf6caad0f3128641aa39db5639
tree: 5374a9c1afcefb70d830e9eb595053f101643123
  1. r21/
  2. r23/
  3. Android.bp
  4. Android.mk
  5. CleanSpec.mk
  6. NOTICE
  7. pylintrc
  8. update.py