RFR: JDK-8213709: jdk/javadoc/doclet/testValueTag/TestValueTagInModule.java missing modules declaration

[Erik Joelsson]

Please review this simple fix for the test 
jdk/javadoc/doclet/testValueTag/TestValueTagInModule.java which adds 
modules declarations necessary to properly compile the @library 
declarations.

Bug: https://bugs.openjdk.java.net/browse/JDK-8213709

Webrev: http://cr.openjdk.java.net/~erikj/8213709/webrev.01/

/Erik