RFR 8141409 Arrays.equals accepting a Comparator

[Paul Sandoz]

Hi,

Please review:

  http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8141409-Arrays-equals-comparator/webrev/ <http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8141409-Arrays-equals-comparator/webrev/>
  https://bugs.openjdk.java.net/browse/JDK-8141409 <https://bugs.openjdk.java.net/browse/JDK-8141409>

This builds on (the already reviewed):

  https://bugs.openjdk.java.net/browse/JDK-8033148 <https://bugs.openjdk.java.net/browse/JDK-8033148>
  http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8033148-Arrays-lexico-compare/webrev/ <http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8033148-Arrays-lexico-compare/webrev/>

and adds yet more methods to Arrays, only two this time though, to fill out the missing gaps related to array equality with a comparator.

In addition i added an Objects.compare method, which simplifies the implementations of some object-bearing methods.

Both additions simplify the specification some object-bearing methods.

Paul.