RFR: JDK-8204969: Asserts in objArrayKlass.cpp need to use _raw variants of obj_addr_at()

[Roman Kennke]

Asserts in objArrayKlass.cpp need to use _raw variants of obj_at_addr()
(in ObjArrayKlass::copy_array), otherwise they go through resolve() and
may get a different copy of the array, and fail the assert.

Bug:
https://bugs.openjdk.java.net/browse/JDK-8204969
Webrev:
http://cr.openjdk.java.net/~rkennke/JDK-8204969/webrev.00/

Can I get a review? Also, does it qualify as trivial?

Thanks!
Roman