StandardError should become an operand which always refers to same value

[enebo]

Originally from #2417. This snippets shows that in MRI StandardError is saved off at bootstrap and is immune to the constant changing. We should make a special operand for this so we can still use it in EQQ instr:

Object.const_set :StandardError, 1

class ExposesJRuby2417 < BasicObject                                               
  def blow_up                                                                      
    begin                                                                          
      ::Kernel.raise "error"                                                       
    rescue 
       puts "rescued"                                                                        
    end                                                                            
  end                                                                              
end                                                                                
ExposesJRuby2417.new.blow_up