IOException "Unable to load OAuth2 connection factory." in TestWebHDFSOAuth2.listStatusReturnsAsExpected

This test is failing consistently in Hadoop-hdfs-trunk and Hadoop-hdfs-trunk-Java8 since September 22.

REGRESSION: org.apache.hadoop.hdfs.web.TestWebHDFSOAuth2.listStatusReturnsAsExpected

Error Message:
Unable to load OAuth2 connection factory.

Stack Trace:
java.io.IOException: Unable to load OAuth2 connection factory.
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(FileInputStream.java:146)
at org.apache.hadoop.security.ssl.ReloadingX509TrustManager.loadTrustManager(ReloadingX509TrustManager.java:164)
at org.apache.hadoop.security.ssl.ReloadingX509TrustManager.<init>(ReloadingX509TrustManager.java:81)
at org.apache.hadoop.security.ssl.FileBasedKeyStoresFactory.init(FileBasedKeyStoresFactory.java:215)
at org.apache.hadoop.security.ssl.SSLFactory.init(SSLFactory.java:131)
at org.apache.hadoop.hdfs.web.URLConnectionFactory.newSslConnConfigurator(URLConnectionFactory.java:135)
at org.apache.hadoop.hdfs.web.URLConnectionFactory.newOAuth2URLConnectionFactory(URLConnectionFactory.java:110)
at org.apache.hadoop.hdfs.web.WebHdfsFileSystem.initialize(WebHdfsFileSystem.java:158)
at org.apache.hadoop.hdfs.web.TestWebHDFSOAuth2.listStatusReturnsAsExpected(TestWebHDFSOAuth2.java:147)