deal with a_constructor in hxb

Author: Simn

src/compiler/hxb/hxbReader.ml

@@ -1589,6 +1589,7 @@ class hxb_reader
 		a.a_read <- self#read_option (fun () -> self#read_field_ref);
 		a.a_write <- self#read_option (fun () -> self#read_field_ref);
 		a.a_call <- self#read_option (fun () -> self#read_field_ref);
+		a.a_constructor <- self#read_option (fun () -> self#read_field_ref);
 
 		a.a_ops <- self#read_list (fun () ->
 			let i = read_byte ch in

src/compiler/hxb/hxbWriter.ml

@@ -1918,6 +1918,7 @@ module HxbWriter = struct
 		Chunk.write_option writer.chunk a.a_read (write_field_ref writer c CfrStatic );
 		Chunk.write_option writer.chunk a.a_write (write_field_ref writer c CfrStatic);
 		Chunk.write_option writer.chunk a.a_call (write_field_ref writer c CfrStatic);
+		Chunk.write_option writer.chunk a.a_constructor (write_field_ref writer c CfrStatic);
 
 		Chunk.write_list writer.chunk a.a_ops (fun (op, cf) ->
 			Chunk.write_u8 writer.chunk (binop_index op);