RUBY-14471: let's use calced_stack_size for step-out

to avoid problems with stepping out of the first call in a call chain

Author: os97673

ext/context.c

@@ -333,12 +333,12 @@ Context_stop_frame(VALUE self, VALUE frame)
   debug_context_t *debug_context;
 
   Data_Get_Struct(self, debug_context_t, debug_context);
-  if(FIX2INT(frame) < 0 && FIX2INT(frame) >= debug_context->stack_size)
+  if(FIX2INT(frame) < 0 && FIX2INT(frame) >= debug_context->calced_stack_size)
     rb_raise(rb_eRuntimeError, "Stop frame is out of range.");
   /* we decrease stack size by frame and 1 because we use stop_frame after
      updating stack size.  If that code will be changed this should be changed accordingly.
    */
-  debug_context->stop_frame = debug_context->stack_size - FIX2INT(frame) - 1;
+  debug_context->stop_frame = debug_context->calced_stack_size - FIX2INT(frame) - 1;
 
   return frame;
 }

ext/debase_internals.c

@@ -298,7 +298,7 @@ process_return_event(VALUE trace_point, void *data)
   /* it is important to check stop_frame after stack size updated
      if the order will be changed change Context_stop_frame accordingly.
   */
-  if(context->stack_size == context->stop_frame)
+  if(context->calced_stack_size == context->stop_frame)
   {
     context->stop_next = 1;
     context->stop_frame = -1;