* dummy-frame.h (dummy_frame_pop): Add prototype.

	* dummy-frame.h (dummy_frame_pop): Add prototype.
	* dummy-frame.c: Include "observer.h".
	(dummy_frame_push): Do not check for stale frames.
	(dummy_frame_pop): New function.
	(cleanup_dummy_frames): New function.
	(_initialize_dummy_frame): Install it as inferior_created observer.

	* frame.h (struct frame_id): Update comments.
	(frame_id_inner): Remove prototype.
	* frame.c (frame_id_inner): Make static.  Add comments.
	(frame_find_by_id): Update frame_id_inner safety net check to avoid
	false positives for targets using non-contiguous stack ranges.
	(get_prev_frame_1): Update frame_id_inner safety net check.
	(frame_pop): Call dummy_frame_pop when popping a dummy frame.

	* stack.c (return_command): Directly pop the selected frame.
	* infrun.c (handle_inferior_event): Remove dead code.
	* i386-tdep.c (i386_push_dummy_call): Update comment.