Request for reviews (XS): 7026631: field _klass is incorrectly set for dual type of TypeAryPtr::OOPS

[Vladimir Kozlov]

http://cr.openjdk.java.net/~kvn/7026631/webrev

Fixed 7026631: field _klass is incorrectly set for dual type of TypeAryPtr::OOPS

TypeAryPtr::klass() method misses the check "this->dual() != TypeAryPtr::OOPS" 
and sets _klass field to dangling ciKlass pointer. As result VM crash when it 
tries to use this cached pointer during an other compilation.