function _flattenBufferIn () {
  if (this._isStreamInput()) {
    this.options.input.buffer = Buffer.concat(this.options.input.buffer);
  }
}
function _flattenBufferIn () {
  if (this._isStreamInput()) {
    this.options.input.buffer = Buffer.concat(this.options.input.buffer);
  }
}
function _flattenBufferIn ( ) { if ( this . _isStreamInput ( ) ) { this . options . input . buffer = Buffer . concat ( this . options . input . buffer ) ; } }
Flattens the array of chunks accumulated in input.buffer.
@private
Flattens the array of chunks accumulated in input . buffer .
Flatten buffer in input