//
// Add boundary-handling to a Leaflet map
//
// The boundary layer allows exactly one boundary at a time and fires events
// (boundarieschange) when this layer changes.
//

L.Map.include({
    boundariesLayer: null,

    _initBoundaries: function () {
        this.boundariesLayer = L.geoJson(null, {
            color: '#FFA813',
            fill: false,
            opacity: 1
        }).addTo(this);
    },

    removeBoundaries: function (data, options) {
        this.boundariesLayer.clearLayers();
        this.fire('boundarieschange');
    },

    updateBoundaries: function (data, options) {
        this.boundariesLayer.clearLayers();
        this.boundariesLayer.addData(data);
        this.fire('boundarieschange');
        if (options.zoomToBounds) {
            this.fitBounds(this.boundariesLayer.getBounds());
        }
    }

});

L.Map.addInitHook('_initBoundaries');

@@ -173,22 +173,20 @@
 //%0A%0A
-L.Map.include(
+var mixin = 
 %7B%0A  
@@ -841,17 +841,155 @@
 %7D%0A%0A%7D
-)
 ;%0A%0A
-L.Map
+module.exports = %7B%0A    initialize: function (mapClass) %7B%0A        mapClass = mapClass %7C%7C L.Map;%0A        mapClass.include(mixin);%0A        mapClass
 .add
@@ -1013,12 +1013,40 @@
 undaries');%0A
+    %7D,%0A%0A    mixin: mixin%0A%7D;%0A

Make it so you have to explicitly initialize the mixin