RFR: 8067295 - Need to port Utils chagnes... 8067307: Need custom classloaders... 8067291: Need additional vm checks...

[Dmitrij Pochepko]

Hi,

Please review changes for
https://bugs.openjdk.java.net/browse/JDK-8067291 - Need additional vm 
checks in jdk/test/lib/testlibrary/jdk/testlibrary/Platform, checking 
which vm is run
https://bugs.openjdk.java.net/browse/JDK-8067295 - Need to port Utils 
chagnes from JDK-8059613 into jdk workspace
https://bugs.openjdk.java.net/browse/JDK-8067307 - Need custom 
classloaders(parent-last and filtering one) for JDK-8066625 in testlibrary

Description: A number of small testlibrary changes needed for further 
test development, 2 of 3 is porn from respective hotspot changes
3rd one (JDK-8067307) introduce 2 classloaders for testlibrary. 1st is 
FilterClassLoader - loads classes using target classloader in case
class name meets provided condition, and using parent otherwise. 2nd is 
ParentLastURLClassLoader which loads classes using provided URL[] with 
fallback to parent,

Webrevs:
http://cr.openjdk.java.net/~iignatyev/dpochepk/8067291/webrev.00/
http://cr.openjdk.java.net/~iignatyev/dpochepk/8067295/webrev.00/
http://cr.openjdk.java.net/~iignatyev/dpochepk/8067307/webrev.00/

Thanks,
Dmitrij