anchor.diff:    final CommonElements _commonElements;
   
     /// Subclasses of [NativeEnqueuerBase] are constructed by the backend.
  -  NativeEnqueuerBase(this._options, this._elementEnvironment,
  -      this._commonElements, this._dartTypes);
  +  NativeEnqueuer(this._options, this._elementEnvironment, this._commonElements,
  +      this._dartTypes);
   
     bool get enableLiveTypeAnalysis => _options.enableNativeLiveTypeAnalysis;
   
  -  @override
  +  /// Called when a [type] has been instantiated natively.
     void onInstantiatedType(InterfaceType type) {
       if (_unusedClasses.remove(type.element)) {
         _registeredClasses.add(type.element);
       }
     }
  +
  +  /// Initial entry point to native enqueuer.
  +  WorldImpact processNativeClasses(Iterable<Uri> libraries);
   
     /// Register [classes] as natively instantiated in [impactBuilder].
     void _registerTypeUses(
  
positive.code:   }
  }
  
  class NativeResolutionEnqueuer extends NativeEnqueuerBase {
    final NativeClassFinder _nativeClassFinder;
  
    /// The set of all native classes.  Each native class is in [nativeClasses]
  
negative.code:     }
    }
  
    /// Registers the [nativeBehavior]. Adds the liveness of its instantiated
    /// types to the world.
    void registerNativeBehavior(
        WorldImpactBuilder impactBuilder, NativeBehavior nativeBehavior, cause) {
      _processNativeBehavior(impactBuilder, nativeBehavior, cause);
  