map(stack) {
    let parsed = fromStackProperty(stack);
    let array = [];
    let lastPromise = null;
    parsed.forEach((item) => {
      lastPromise = this._lastPromise
        .then(() => this.getSourceMap(item.url), null, 'ember-inspector')
        .then((smc) => {
          if (smc) {
            let source = smc.originalPositionFor({
              line: item.line,
              column: item.column,
            });
            source.fullSource = relativeToAbsolute(item.url, source.source);
            array.push(source);
            return array;
          }
        }, null);
      this._lastPromise = lastPromise;
    });
    return Promise.resolve(lastPromise).catch(function (e) {
      if (e === notFoundError) {
        return null;
      }
      throw e;
    });
  }
Returns a promise that resolves to an array
of mapped sourcew.

@param  {String} stack The stack trace
@return {RSVP.Promise}