RFR JDK-8171385: jshell tool: unresponsive to ctrl-C in input wait on Windows

[Robert Field]

Looks good.

Nit: address, or not, currentState no longer needs to be a variable


> On Jan 9, 2017, at 8:01 AM, Jan Lahoda <jan.lahoda at oracle.com> wrote:
> 
> Hi,
> 
> I'd like to ask for a review of a fix for:
> https://bugs.openjdk.java.net/browse/JDK-8171385
> 
> Webrev:
> http://cr.openjdk.java.net/~jlahoda/8171385/webrev.00/
> 
> The problem is that the state of the StopDetectingInputStream changes while it is waiting for data. And when the first character read is Ctrl-C, the cancel might be sent the wrong direction. The proposed fix is to check the state again after reading from the input.
> 
> Jan