HDFS-10843. Add missing file to commit 4b5806217e6846bcecc6480af46c0e70102daac0.

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/test/GenericTestUtils.java

@@ -179,6 +179,9 @@ public abstract class GenericTestUtils {
       return c;
     }
     
+    public static LogCapturer captureLogs(Logger l) {
+      return new LogCapturer(l);
+    }
 
     private LogCapturer(Logger logger) {
       this.logger = logger;