RFR 8172201 Replace assert of return type in VarHandle.AccessMode with test

[Paul Sandoz]

Hi,

Please review the following which removes an assert statement from the constructor of VarHandle.AccessMode and replaces it with a test:

  http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8172201-vh-accessmode-return-type-assert/webrev/jdk.patch <http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8172201-vh-accessmode-return-type-assert/webrev/jdk.patch>

The execution of the assert statement, with it’s use of core reflection, could potentially interfere with the execution of other tests and result in circular dependency issues if assertions are enabled.

Thanks,
Paul.