Update dependency com.google.protobuf:com.google.protobuf.gradle.plugin to v0.8.15 (#674)
Update dependency com.google.protobuf:com.google.protobuf.gradle.plugin to v0.8.15 (#674)


GoogleCloudPlatform/cloud-ops-sandbox,GoogleCloudPlatform/cloud-ops-sandbox,GoogleCloudPlatform/cloud-ops-sandbox,GoogleCloudPlatform/cloud-ops-sandbox,GoogleCloudPlatform/cloud-ops-sandbox,GoogleCloudPlatform/cloud-ops-sandbox,GoogleCloudPlatform/cloud-ops-sandbox