RFR: 8166289: RuntimeException: canRead() reports false for reading from the same module: expected true, was false

[Alexander Kulyakhtin]

Hi,

Could you, please, review these test-only changes

CR: https://bugs.openjdk.java.net/browse/JDK-8166289 "RuntimeException: canRead() reports false for reading from the same module: expected true, was false"
Webrev: http://cr.openjdk.java.net/~akulyakh/8166289/

The fix restores the changes for https://bugs.openjdk.java.net/browse/JDK-8165017, which were backed out with https://bugs.openjdk.java.net/browse/JDK-8166312, due to the test failure.
The test failure have never been reproduced after extensive testing. This fix is trying to restore the changes adding a more correct verification of the CANREAD command, as well as some additional logging in case the test fails again. 

Best regards,
Alexander