Have CXXDeleteExpr::getDestroyedType return the actual destroyed type

in more situations.  In particular, for code like

   template<class T> void Fn() { T* x; delete x; }

getDestroyedType() will now return T rather than T*, as it would
before this change.  On the other hand, for code like this:

   template<class T> void Fn() { T x; delete x; }

getDestroyedType() will return an empty QualType(), since it doesn't
know what the actual destroyed type would be.  Previously, it would
return T.

OKed by rjmccall

llvm-svn: 119334