[enhancement] Getting e.RawData still decodes byte array to string internally

[vritme]

In this file: https://github.com/sta/websocket-sharp/blob/master/websocket-sharp/MessageEventArgs.cs

public byte[] RawData {
  get {
    setData ();

    return _rawData;
  }
}

e.RawData property of websocket message event calls the same setData() method, which is used for e.Data property:

public string Data {
  get {
    setData ();

    return _data;
  }
}

And setData() method, when called for the first time for a given event object and if opcode is not Binary, unconditionally tries to decode byte array to string via TryGetUTF8DecodedString() method in order to prepare string _data field for e.Data property to use (even if called from e.DataRaw, where byte array to string decoding is not needed):

private void setData ()
{
  if (_dataSet)
    return;

  if (_opcode == Opcode.Binary) {
    _dataSet = true;

    return;
  }

  string data;

  if (_rawData.TryGetUTF8DecodedString (out data))
    _data = data;

  _dataSet = true;
}

Calling _rawData.TryGetUTF8DecodedString on e.RawData property call prior to returning just _rawData byte array breaks the point of using e.RawData property for the purpose of message processing speedup via avoiding string allocation and byte array to string conversion.

I suppose the e.RawData property should be reworked like this:

public byte[] RawData {
  get {
    return _rawData;
  }
}

[vritme]

By the way, thanks for the lib, it's awesome.