Bug 732665 - Disable a few test on mac. r=tbsaunde,me

These tests trigger very slow infinite recursion in the status quo. With the
existing stack quotas, they always (or usually) hit the native stack limit
before the test times out, causing them to be green on tinderbox. But when
we bump the debug mac stack limit, they end up timing out. We have bugs on
file for the various issues, but let's not let them block this landing.
Bug 732665 - Introduce a mechanism for specifying different stack limits for system, trusted, and untrusted code. r=luke

We kind of cop out for ion and PJS stuff. We should at least have a good story
for ion, but it probably needs to be done with someone with more jit familiarity
than I have.

The uninlined function call in JS_CHECK_RECURSION is unfortunate. We could fix
this either by separating the jsfriendapi JS_CHECK_RECURSION from the internal
one, or moving the appropriate stuff into friend fields.
Bug 732665 - Clean up and clarify the stack sizing logic. r=luke

The only change in behavior here is that we give the osx check higher precedence
than the DEBUG check, meaning that we end up with 7MB stacks on osx debug rather
than 4MB stacks. But this seems strictly better given the logic involved here.
Bug 732665 - Use separate stack depths for XPConnect JS. r=luke
Bug 732665 - Tests. r=luke