[12] RFR: 8214827: Incorrect call ClassLoaders.toFileURL("jrt:/java.compiler")

[Jiangli Zhou]

Please review the bug fix for 
SystemDictionaryShared::get_shared_protection_domain(). When 
jrt:/<module> location is given, a null URL (due to the error in 
ClassLoaders.toFileURL) is used for the CodeSource, which results a 
wrong ProtectionDomain being used for the archived app/platform class 
from the runtime image. The granted permission is minimum in that case.

This turns out to be an issue that's hidden for a long time. The 
JimageClassProtDomain.java test has been outdated and fails to detect 
the issue (I'm the guilt one). Please see the comments in the bug for 
more details. Thanks Martin for finding the issue, and David, Alan and 
Mandy for discussions.

webrev: http://cr.openjdk.java.net/~jiangli/8214827/webrev.01/

bug: https://bugs.openjdk.java.net/browse/JDK-8214827

Tested with appcds tests locally. Tested tier1-2. Tier3 is still in 
progress.

Thanks,

Jiangli