7142847: TEST_BUG: java/nio/file/WatchService/SensitivityModifier.java has incorrect @run tag, runs Basic

[Alan Bateman]

This is an update to two of the tests for java.nio.file.WatchService. In 
the case of SensitivityModifier.java, it specifies the wrong class name 
in the @run tag and so is running the Basic test. The change to 
Basic.java is to use nanoTime rather than currentTimeMillis when testing 
the duration of the poll method. The webrev with the changes is here:

http://cr.openjdk.java.net/~alanb/7142847/webrev/

Thanks,
Alan.