[user32] Add DECLSPEC_NOINLINE, use it on call_hook_proc()

[Dan Kegel]

On Fri, Apr 19, 2013 at 10:38 AM, Dan Kegel <dank at kegel.com> wrote:
> Hooking is a fragile business.  Somebody somewhere is probably
> making assumptions about how hooking works (like, how many stack
> frames are pushed), and inlining call_hook_proc probably violates one
> of those assumptions.

That said, this is all a big guess.  It would be nice to have a
test that demonstrated the problem.  It's up to Alexandre to
decide whether making a couple apps happier is evidence
enough that disabling inlining of this one function is a good idea.
- Dan