[12] (S) RFR 8206122 : Use Queue in place of ArrayList when need to remove first element

[Ivan Gerasimov]

Hello!

It is a tiny optimization.

There are a couple of places where ArrayList is used as FIFO: elements 
are appended to the end, and removed from the head.

ArrayDeque would be more efficient to use.

Would you please help review?

BUG: https://bugs.openjdk.java.net/browse/JDK-8206122

Webrev: http://cr.openjdk.java.net/~igerasim/8206122/00/webrev/

Thanks in advance!

-- 
With kind regards,
Ivan Gerasimov