code: function getKeyCustomizationLayer(layerName) {
    var cust = KeyBinding.prototype["ace.ext.keys.customized"] || (KeyBinding.prototype["ace.ext.keys.customized"] = []);
    var found;
    for (var i = cust.length-1; i >= 0; i--) { if (cust[i].layerName === layerName) {found = cust[i]; break; }; }
    return found ? found.bindingsSpec : null;
  }
docs: KeyBinding.prototype["ace.ext.keys.customized"] this.aceEditor.keyBinding.$handlers