fix parsing error in p_constructor_declaration

 def p_constructor_declaration(self, p):
      '''constructor_declaration : constructor_header method_body'''
           p[0] = ConstructorDeclaration(p[1], p[2],
           modifiers=p[1]['modifiers'],
           ....

to

 def p_constructor_declaration(self, p):
      '''constructor_declaration : constructor_header method_body'''
           p[0] = ConstructorDeclaration(p[1]['name'], p[2],
           modifiers=p[1]['modifiers'],
           ....

I think it's much more reasonable :)