[PATCH] Push a LambdaScopeInfo on after introducer, in anticipation for generic lambdas

[Faisal Vali]

Hi Richard,
    Per your suggestion here:
http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20130624/082607.html,
the attached patch pushes a lambda scope info on right after
the introducer is parsed.

I've also added some basic support for passing the
TemplateParameterDepth from the parser into Sema.
I will obviously build on this with generic lambdas.

Currently, in the transformer, we don't really need the
template depth, so i pass in -1 converted to an unsigned.
Is there a better way to do this - should i make AutoTPDepth
optional with the lambdascopeinfo (seems a little overkill?)

There is no functionality change here, so if you approve, perhaps
i can commit this change on its own?

thanks!

Faisal Vali