hg: jdk/jdk10: 8188649: javadoc -encoding doesn't work when using the old doclet API

[jonathan.gibbons at oracle.com]

Changeset: cb7926b6b3d6
Author:    jjg
Date:      2018-01-05 12:41 -0800
URL:       http://hg.openjdk.java.net/jdk/jdk10/rev/cb7926b6b3d6

8188649: javadoc -encoding doesn't work when using the old doclet API
Reviewed-by: ksrini

! src/jdk.javadoc/share/classes/com/sun/tools/javadoc/main/ToolOption.java
+ test/langtools/jdk/javadoc/tool/EncodingTest.java
+ test/langtools/tools/javadoc/EncodingTest.java