fix SnapshotDeletionPolicy to remove the test dir if present to prevent false failures

git-svn-id: https://svn.apache.org/repos/asf/lucene/java/trunk@764579 13f79535-47bb-0310-9956-ffa450edef68

src/test/org/apache/lucene/TestSnapshotDeletionPolicy.java

@@ -52,6 +52,8 @@ public class TestSnapshotDeletionPolicy extends LuceneTestCase
   public void testSnapshotDeletionPolicy() throws Exception {
     File dir = new File(System.getProperty("tempDir"), INDEX_PATH);
     try {
+      // Sometimes past test leaves the dir
+      _TestUtil.rmDir(dir);
       Directory fsDir = FSDirectory.getDirectory(dir);
       runTest(fsDir);
       fsDir.close();