Fix -Wnullable-to-nonnull-conversion errors

Fix the build errors like https://android-build.googleplex.com/builds/pending/P56284860/aosp_arm64-userdebug/latest/view/logs/build.log?legacy

Bug: None
Test: mm
Change-Id: Ib49e72e456bbf4d0405dcf227881579df149cdfd
1 file changed
tree: 980f6bac8f223eb4ea4071bbcc0dcac1072a68b4
  1. client/
  2. include/
  3. netutils_wrappers/
  4. server/
  5. tests/
  6. .editorconfig
  7. Android.bp
  8. NOTICE
  9. OWNERS
  10. PREUPLOAD.cfg
  11. TEST_MAPPING