When checking javadoc refactoring, it is convenient to compare the before-and-after output of all the tests. By default, javadoc writes hidden timestamps in the generated files, and so to be able to compare befopre-and-after, it is convenient to use shell scriipts to "zap" these timestamps.

But TestDocEncoding.java writes files with Cp930 encoding, which makes it much harder to remove the generated timestamp. In this exceptional case, we should run javadoc with -notimestamps.