support task cancel

Author: weizijun

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/rollup/action/RollupShardStatus.java

@@ -107,12 +107,8 @@ public void init(AtomicLong numReceived, AtomicLong numSent, AtomicLong numIndex
         this.numFailed = numFailed;
     }
 
-    public Status getStatus() {
-        return status;
-    }
-
-    public void setStatus(Status status) {
-        this.status = status;
+    public void setFinished() {
+        this.status = Status.FINISHED;
     }
 
     public boolean isCancelled() {

x-pack/plugin/rollup/src/main/java/org/elasticsearch/xpack/rollup/v2/RollupShardIndexer.java

@@ -166,6 +166,8 @@ public RollupIndexerAction.ShardRollupResponse execute() throws IOException {
                     + "]."
             );
         }
+
+        status.setFinished();
         return new RollupIndexerAction.ShardRollupResponse(indexShard.shardId(), numIndexed.get());
     }