hg: jdk9/dev/langtools: 8175047: javadoc should support --help-extra as a synonym for -X

[jonathan.gibbons at oracle.com]

Changeset: 1eca2a674d44
Author:    jjg
Date:      2017-02-15 18:30 -0800
URL:       http://hg.openjdk.java.net/jdk9/dev/langtools/rev/1eca2a674d44

8175047: javadoc should support --help-extra as a synonym for -X
Reviewed-by: ksrini

! src/jdk.javadoc/share/classes/jdk/javadoc/internal/tool/ToolOption.java
! src/jdk.javadoc/share/classes/jdk/javadoc/internal/tool/resources/javadoc.properties
! test/jdk/javadoc/doclet/testXOption/TestXOption.java