Property definitions

nitc $ FlowVisitor :: merge_breaks
	fun merge_breaks(escapemark: nullable EscapeMark)
	do
		if escapemark == null then return
		for b in escapemark.escapes do
			var before = b.before_flow_context
			if before == null then continue # Forward error
			self.make_merge_flow(self.current_flow_context, before)
		end
	end
src/semantize/flow.nit:175,2--183,4