function success(image) {
    if (!defined(image)) {
      return failure();
    }

    imagery.image = image;
    imagery.state = ImageryState.RECEIVED;
    imagery.request = undefined;

    TileProviderError.reportSuccess(that._requestImageError);
  }
Request a particular piece of imagery from the imagery provider.  This method handles raising an
error event if the request fails, and retrying the request if necessary.

@private

@param {Imagery} imagery The imagery to request.