js/libs/ember-1.5.1.js
function(toPath, fromPath) {
  this._direction = 'fwd';
  this._from = fromPath;
  this._to   = toPath;
  this._directionMap = Ember.Map.create();
}
function(toPath, fromPath) {
  this._direction = 'fwd';
  this._from = fromPath;
  this._to   = toPath;
  this._directionMap = Ember.Map.create();
}
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