Remove the now unnecessary "use_draw_order" code path?

[rahulporuri]

enable/enable/component.py

Lines 938 to 941 in d9e95c5

	# This hasattr check is necessary to ensure compatibility with Chaco
	# components.
	if not getattr(self, "use_draw_order", True):
	self._old_dispatch(event, suffix)

This seems to have been introduced in 9977aa5 and has been available in enable since version 3. I think it is safe to remove it now.

[rahulporuri]

see related chaco issue enthought/chaco#659