[8u20] backport request for 8040656: Classes with overriden methods with covariant returns return random read methods

[sergey malenkov]

Hello,

This is a direct backport from jdk 9 to jdk 8u.

Issue: https://bugs.openjdk.java.net/browse/JDK-8040656
Webrev: http://cr.openjdk.java.net/~malenkov/8040656.9.0/
Changeset: http://hg.openjdk.java.net/jdk9/client/jdk/rev/a8ca8e71ce49
Reviewers: Alexandr Scherbatiy, Sergey Bylokhov

Thanks,
SAM