RFR 8150860: Mach 5 tier1 test started failing - jdk/jshell/ComputeFQNsTest.java (after 8131027/8150814)

[Jan Lahoda]

Hi,

I'd like to ask for a review of fix for:
https://bugs.openjdk.java.net/browse/JDK-8150860

Webrev:
http://cr.openjdk.java.net/~jlahoda/8150860/webrev.00/

The reason why the test was failing on Windows is that the test is 
placing Path.toString() into a string literal and then compiling it. But 
as Paths on Windows contain '\', this lead to compilation errors due to 
invalid escape sequences. The solution is to escape '\'. The test should 
also not show a more appropriate exception than below when failing for a 
reason like this.

Thanks,
     Jan