Addendum of HDFS-10722 to include HDFS-7964 logic.

(cherry picked from commit 4a8e6dc02f)
(cherry picked from commit 3b2554f3b0)
(cherry picked from commit c2bb9bf00c)

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestEditLog.java

@@ -591,8 +591,12 @@ public class TestEditLog {
 
       // Log an edit from thread A
       doLogEdit(threadA, editLog, "thread-a 1");
-      assertEquals("logging edit without syncing should do not affect txid",
-          1, editLog.getSyncTxId());
+      // async log is doing batched syncs in background.  logSync just ensures
+      // the edit is durable, so the txid may increase prior to sync
+      if (!useAsyncEditLog) {
+        assertEquals("logging edit without syncing should do not affect txid",
+            1, editLog.getSyncTxId());
+      }
       // logSyncAll in Thread B
       doCallLogSyncAll(threadB, editLog);
       assertEquals("logSyncAll should sync thread A's transaction",