objc/objc++: switch all testcases to Modern Objective-C runtime API

[Mike Stump]

On Jun 6, 2011, at 10:21 AM, Nicola Pero wrote:
> This patch switches all the testcases in the ObjC/ObjC++ testsuite to use the
> Modern Objective-C runtime API when executing with the GNU runtime.
> OK to commit ?

Ok, from me with one possible exception, I'd like Iain or Jack to weigh in on wether it should go in before they have a chance to test it on pre 10.6 systems.  I'm fine with it going in before or after, as we're in stage 1 and I think there is plenty of time to address any pre 10.6 fallout.  If it goes in sooner, we'll get 10.5 coverage with Geoff's tester.