review (XS) for 7019819: bare oop in ciField

[Tom Rodriguez]

http://cr.openjdk.java.net/~never/7019819

7019819: bare oop in ciField
Reviewed-by:

This appears to be a long standing issue though it was previously
unlikely to occur.  There's a bare oop in initialize_from over a call
to ciField::type which may call compute_type, which make call into
ciEnv::get_klass_by_name_impl where a safepoint could potentially
occur.  The fix for 6354181 added acquire of the Compile_lock which
made it more likely that we might safepoint here.  The fix is properly
handleize the oop over the call.  Tested with failing test from nightly.