fix #574, captureStackTrace will have additional stackframe from Zone…

[JiaLiPassion]

Fix #574, from zone.js 0.7.x, we have a patched ZoneAwareError, and we patch everything from native Error includes captureStackTrace and prepareStackTrace like this.

      if (NativeError.hasOwnProperty('captureStackTrace')) {
    Object.defineProperty(ZoneAwareError, 'captureStackTrace', {
      // add named function here because we need to remove this
      // stack frame when prepareStackTrace below
      value: function(targetObject: Object, constructorOpt?: Function) {
        NativeError.captureStackTrace(targetObject, constructorOpt);
      }
    });
  }

It works but will add an additional stack frame, which is the patched function named
value above. So it will break binding.js which try to find the current loaded js filename.

So in this fix, I change the patch function to a named function(zoneCaptureStackTrace),
and remove this stack information when call prepareStackTrace.