tree acf7cf148b282b8d3330ff1e17f73da74cf70824
parent 0b4bdc0fa83eaae695732271dd073cdf6a9595fc
author Haibo Huang <hhb@google.com> 1559194654 -0700
committer Haibo Huang <hhb@google.com> 1559754705 +0000

Fix compilation error with new kotlinc

These code failed with kotlinc v1.3.31. The new compiler is able to
understand Java @NotNull.

Exempt-From-Owner-Approval: Fix compilation issue in new compiler.
Test: build
Change-Id: I4df49514008588ec16698f1f5ca11bca151a12a9