Review Request JDK-8200121: Remove unused qualified exports in java.base

[mandy chung]

A simple cleanup to remove unused qualified exports in java.base.

The webrev also includes a fix for JDK-8205116 (jdeps --system 
$java.home fails) that I uncovered through this process where I ran 
`jdeps --check java.base --system $java.home` on the JDK binaries on 
several platforms.

Webrev at:
http://cr.openjdk.java.net/~mchung/jdk11/webrevs/8200121/webrev.00/

Mandy