RFR: JDK-8223536 jdk/javadoc/doclet/MetaTag/MetaTag.java still fails when run across midnight

[Jonathan Gibbons]

Please review a fix for a problem that occurs when a test is run across 
midnight.

Although it is difficult to confirm the root cause, and equally 
difficult to test, the root cause is believed to be a static final 
instance of java.util.Calendar that is used to obtain the date written 
into the generated files, and which is subsequently verified by tests. 
When javadoc is run multiple times in the same JVM, as will occur when 
running the MetaTag.java test, the static final Calendar may be 
initialized to a time that is outside the range checked by the test.

The fix is to replace the static instance by a non-static instance 
created in HtmlConfiguration.

The fix is noreg-hard, because it can only be fully tested by running 
within milliseconds of midnight. It's remarkable that this has actually 
occurred multiple times in productio build/test runs.

-- Jon


JBS: https://bugs.openjdk.java.net/browse/JDK-8223536
Webrev: http://cr.openjdk.java.net/~jjg/8223536/webrev/