RFR: 8177069: File separator mismatch on Win-64

[Rickard Bäckman]

Hi, can I please have this patch reviewed?

With AOT being ported to Windows some of the file path stuff had to be
updated.

Webrev: http://cr.openjdk.java.net/~rbackman/8177069.2/
Bugs: https://bugs.openjdk.java.net/browse/JDK-8177069

Thanks
/R