Cleaned up the inline stack frame code one more time to prepare for inlined

code stepping. Also we now store the stack frames for the current and previous
stops in the thread in std::auto_ptr objects. When we create a thread stack
frame list we pass the previous frame into it so it can re-use the frames
and maintain will allow for variable changes to be detected. I will implement
the stack frame reuse next.

llvm-svn: 112152