RFR 8024341: j.u.regex.Pattern.splitAsStream() doesn't correspond to split() method if using an example from the spec

[Paul Sandoz]

Hi,

http://cr.openjdk.java.net/~psandoz/tl/JDK-8024341-pattern-splitAsStream/webrev/

This fixes an issue with Pattern.splitAsStream reporting empty trailing elements and aligns with the functionality of Pattern.split(CharSequence input).

The matching iterator passed to the stream was updated to aggressively consume and keep a count of a sequence of empty matching elements such that those elements can either be reported if not trailing, or discarded if trailing.

Paul.