WebRTC refactor. Data channels, STUN/TURN support.

A big refactor to the WebRTC module. API is now considered quite stable.

Highlights:

- Renamed `WebRTCPeer` to `WebRTCPeerConnection`.
- `WebRTCPeerConnection` no longer act as `PacketPeer`, it only handle the connection itself (a bit like `TCP_Server`)
- Added new `WebRTCDataChannel` class which inherits from `PacketPeer` to handle data transfer.
- Add `WebRTCPeerConnection.initialize` method to create a new connection with the desired configuration provided as dictionary ([see MDN docs](https://developer.mozilla.org/en-US/docs/Web/API/RTCPeerConnection/RTCPeerConnection#RTCConfiguration_dictionary)).
- Add `WebRTCPeerConnection.create_data_channel` method to create a data channel for the given connection. The connection must be in `STATE_NEW` as specified by the standard ([see MDN docs for options](https://developer.mozilla.org/en-US/docs/Web/API/RTCPeerConnection/createDataChannel#RTCDataChannelInit_dictionary)).
- Add a `data_channel_received` signal to `WebRTCPeerConnection` for in-band (not negotiated) channels.
- Renamed `WebRTCPeerConnection` `offer_created` signal to `session_description_created`.
- Renamed `WebRTCPeerConnection` `new_ice_candidate` signal to `ice_candidate_created`

1 files changed, 64 insertions, 0 deletions

diff --git a/modules/webrtc/webrtc_data_channel.cpp b/modules/webrtc/webrtc_data_channel.cpp
new file mode 100644
index 0000000000..2bd30e68f5
--- /dev/null
+++ b/modules/webrtc/webrtc_data_channel.cpp
@@ -0,0 +1,64 @@
+/*************************************************************************/
+/*  webrtc_data_channel.cpp                                              */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2019 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "webrtc_data_channel.h"
+
+void WebRTCDataChannel::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("poll"), &WebRTCDataChannel::poll);
+	ClassDB::bind_method(D_METHOD("close"), &WebRTCDataChannel::close);
+
+	ClassDB::bind_method(D_METHOD("was_string_packet"), &WebRTCDataChannel::was_string_packet);
+	ClassDB::bind_method(D_METHOD("set_write_mode", "write_mode"), &WebRTCDataChannel::set_write_mode);
+	ClassDB::bind_method(D_METHOD("get_write_mode"), &WebRTCDataChannel::get_write_mode);
+	ClassDB::bind_method(D_METHOD("get_ready_state"), &WebRTCDataChannel::get_ready_state);
+	ClassDB::bind_method(D_METHOD("get_label"), &WebRTCDataChannel::get_label);
+	ClassDB::bind_method(D_METHOD("is_ordered"), &WebRTCDataChannel::is_ordered);
+	ClassDB::bind_method(D_METHOD("get_id"), &WebRTCDataChannel::get_id);
+	ClassDB::bind_method(D_METHOD("get_max_packet_life_time"), &WebRTCDataChannel::get_max_packet_life_time);
+	ClassDB::bind_method(D_METHOD("get_max_retransmits"), &WebRTCDataChannel::get_max_retransmits);
+	ClassDB::bind_method(D_METHOD("get_protocol"), &WebRTCDataChannel::get_protocol);
+	ClassDB::bind_method(D_METHOD("is_negotiated"), &WebRTCDataChannel::is_negotiated);
+
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "write_mode", PROPERTY_HINT_ENUM), "set_write_mode", "get_write_mode");
+
+	BIND_ENUM_CONSTANT(WRITE_MODE_TEXT);
+	BIND_ENUM_CONSTANT(WRITE_MODE_BINARY);
+
+	BIND_ENUM_CONSTANT(STATE_CONNECTING);
+	BIND_ENUM_CONSTANT(STATE_OPEN);
+	BIND_ENUM_CONSTANT(STATE_CLOSING);
+	BIND_ENUM_CONSTANT(STATE_CLOSED);
+}
+
+WebRTCDataChannel::WebRTCDataChannel() {
+}
+
+WebRTCDataChannel::~WebRTCDataChannel() {
+}