HDFS-9580. TestComputeInvalidateWork#testDatanodeReRegistration failed due to unexpected number of invalidate blocks. Contributed by Wei-Chiu Chuang.

Change-Id: I9411dfb1dd4605cbcc515ca3361218d35d7c5fe3
(cherry picked from commit 0087734cc1e18e029ea39f06ca25c8a7d60af004)

Conflicts:

	hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/blockmanagement/TestComputeInvalidateWork.java

@@ -146,6 +146,7 @@ public class TestComputeInvalidateWork {
     // Create a file and shutdown the DNs, which populates InvalidateBlocks
     DFSTestUtil.createFile(dfs, path, dfs.getDefaultBlockSize(),
         (short) NUM_OF_DATANODES, 0xED0ED0);
+    DFSTestUtil.waitForReplication(dfs, path, (short) NUM_OF_DATANODES, 12000);
     for (DataNode dn : cluster.getDataNodes()) {
       dn.shutdown();
     }