Version management: prep for 1.9.0 release

Author: dhalperi

sdk/src/main/java/com/google/cloud/dataflow/sdk/runners/DataflowPipelineRunner.java

@@ -222,9 +222,9 @@ public class DataflowPipelineRunner extends PipelineRunner<DataflowPipelineJob>
   // Default Docker container images that execute Dataflow worker harness, residing in Google
   // Container Registry, separately for Batch and Streaming.
   public static final String BATCH_WORKER_HARNESS_CONTAINER_IMAGE
-      = "dataflow.gcr.io/v1beta3/java-batch:1.8.1";
+      = "dataflow.gcr.io/v1beta3/java-batch:1.9.0";
   public static final String STREAMING_WORKER_HARNESS_CONTAINER_IMAGE
-      = "dataflow.gcr.io/v1beta3/java-streaming:1.8.1";
+      = "dataflow.gcr.io/v1beta3/java-streaming:1.9.0";
 
   // The limit of CreateJob request size.
   private static final int CREATE_JOB_REQUEST_LIMIT_BYTES = 10 * 1024 * 1024;