RFR: 8200664: fix broken links in java.base docs

[Jonathan Gibbons]

Please review a small update to fix some broken links in the java.base 
API docs.

The change is necessary because when generating HTML 5 output, javadoc
no longer has to encode method signatures into the restricted set of 
characters
available in HTML 4 names.

JBS: https://bugs.openjdk.java.net/browse/JDK-8200664
Webrev: http://cr.openjdk.java.net/~jjg/8200664/webrev.00/

-- Jon