Fixed an issue where StackFrame::GetValueForVariableExpressionPath(...)

was previously using the entire frame variable list instead of using the
in scope variable list. I added a new function to a stack frame:

	lldb::VariableListSP
	StackFrame::GetInScopeVariableList (bool get_file_globals);

This gets only variables that are in scope and they will be ordered such
that the variables from the current scope are first.

llvm-svn: 136745