Merge branch 'stable-3.0' into stable-3.1 * stable-3.0: Upgrade bazlets to latest stable-2.16 to build with 2.16.18 API Bump Bazel version to 3.1.0 Bump Bazel version to 3.0.0 Change-Id: I59a90586ced4ad65788831d667a45cd19b9dfb63