Move talk/app/webrtc to webrtc/api

The previously disabled warnings that were inherited from
talk/build/common.gypi are now replaced by target-specific disabling
of only the failing warnings. Additional disabling was needed since the stricter
compilation warnings that applies to code in webrtc/.

License headers will be updated in a follow-up CL.

Other modifications:
* Updated the header guards.
* Sorted the includes using chromium/src/tools/sort-headers.py
  except for these files:
  talk/app/webrtc/peerconnectionendtoend_unittest.cc
  talk/app/webrtc/java/jni/androidmediadecoder_jni.cc
  talk/app/webrtc/java/jni/androidmediaencoder_jni.cc
  webrtc/media/devices/win32devicemanager.cc

The HAVE_SCTP define was added for the peerconnection_unittests target
in api_tests.gyp.

I also checked that none of
SRTP_RELATIVE_PATH
HAVE_SRTP
HAVE_WEBRTC_VIDEO
HAVE_WEBRTC_VOICE
were used by the talk/app/webrtc code.

For Chromium, the following changes will need to be applied to the roll CL that updates the
DEPS for WebRTC and libjingle:
https://codereview.chromium.org/1615433002

BUG=webrtc:5418
NOPRESUBMIT=True
R=deadbeef@webrtc.org, pthatcher@webrtc.org, tommi@webrtc.org

Review URL: https://codereview.webrtc.org/1610243002 .

Cr-Commit-Position: refs/heads/master@{#11545}
diff --git a/webrtc/api/sctputils.cc b/webrtc/api/sctputils.cc
new file mode 100644
index 0000000..84cb293
--- /dev/null
+++ b/webrtc/api/sctputils.cc
@@ -0,0 +1,205 @@
+/*
+ * libjingle
+ * Copyright 2013 Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "webrtc/api/sctputils.h"
+
+#include "webrtc/base/buffer.h"
+#include "webrtc/base/bytebuffer.h"
+#include "webrtc/base/logging.h"
+
+namespace webrtc {
+
+// Format defined at
+// http://tools.ietf.org/html/draft-ietf-rtcweb-data-protocol-01#section
+
+static const uint8_t DATA_CHANNEL_OPEN_MESSAGE_TYPE = 0x03;
+static const uint8_t DATA_CHANNEL_OPEN_ACK_MESSAGE_TYPE = 0x02;
+
+enum DataChannelOpenMessageChannelType {
+  DCOMCT_ORDERED_RELIABLE = 0x00,
+  DCOMCT_ORDERED_PARTIAL_RTXS = 0x01,
+  DCOMCT_ORDERED_PARTIAL_TIME = 0x02,
+  DCOMCT_UNORDERED_RELIABLE = 0x80,
+  DCOMCT_UNORDERED_PARTIAL_RTXS = 0x81,
+  DCOMCT_UNORDERED_PARTIAL_TIME = 0x82,
+};
+
+bool IsOpenMessage(const rtc::Buffer& payload) {
+  // Format defined at
+  // http://tools.ietf.org/html/draft-jesup-rtcweb-data-protocol-04
+
+  rtc::ByteBuffer buffer(payload);
+  uint8_t message_type;
+  if (!buffer.ReadUInt8(&message_type)) {
+    LOG(LS_WARNING) << "Could not read OPEN message type.";
+    return false;
+  }
+  return message_type == DATA_CHANNEL_OPEN_MESSAGE_TYPE;
+}
+
+bool ParseDataChannelOpenMessage(const rtc::Buffer& payload,
+                                 std::string* label,
+                                 DataChannelInit* config) {
+  // Format defined at
+  // http://tools.ietf.org/html/draft-jesup-rtcweb-data-protocol-04
+
+  rtc::ByteBuffer buffer(payload);
+  uint8_t message_type;
+  if (!buffer.ReadUInt8(&message_type)) {
+    LOG(LS_WARNING) << "Could not read OPEN message type.";
+    return false;
+  }
+  if (message_type != DATA_CHANNEL_OPEN_MESSAGE_TYPE) {
+    LOG(LS_WARNING) << "Data Channel OPEN message of unexpected type: "
+                    << message_type;
+    return false;
+  }
+
+  uint8_t channel_type;
+  if (!buffer.ReadUInt8(&channel_type)) {
+    LOG(LS_WARNING) << "Could not read OPEN message channel type.";
+    return false;
+  }
+
+  uint16_t priority;
+  if (!buffer.ReadUInt16(&priority)) {
+    LOG(LS_WARNING) << "Could not read OPEN message reliabilility prioirty.";
+    return false;
+  }
+  uint32_t reliability_param;
+  if (!buffer.ReadUInt32(&reliability_param)) {
+    LOG(LS_WARNING) << "Could not read OPEN message reliabilility param.";
+    return false;
+  }
+  uint16_t label_length;
+  if (!buffer.ReadUInt16(&label_length)) {
+    LOG(LS_WARNING) << "Could not read OPEN message label length.";
+    return false;
+  }
+  uint16_t protocol_length;
+  if (!buffer.ReadUInt16(&protocol_length)) {
+    LOG(LS_WARNING) << "Could not read OPEN message protocol length.";
+    return false;
+  }
+  if (!buffer.ReadString(label, (size_t) label_length)) {
+    LOG(LS_WARNING) << "Could not read OPEN message label";
+    return false;
+  }
+  if (!buffer.ReadString(&config->protocol, protocol_length)) {
+    LOG(LS_WARNING) << "Could not read OPEN message protocol.";
+    return false;
+  }
+
+  config->ordered = true;
+  switch (channel_type) {
+    case DCOMCT_UNORDERED_RELIABLE:
+    case DCOMCT_UNORDERED_PARTIAL_RTXS:
+    case DCOMCT_UNORDERED_PARTIAL_TIME:
+      config->ordered = false;
+  }
+
+  config->maxRetransmits = -1;
+  config->maxRetransmitTime = -1;
+  switch (channel_type) {
+    case DCOMCT_ORDERED_PARTIAL_RTXS:
+    case DCOMCT_UNORDERED_PARTIAL_RTXS:
+      config->maxRetransmits = reliability_param;
+      break;
+    case DCOMCT_ORDERED_PARTIAL_TIME:
+    case DCOMCT_UNORDERED_PARTIAL_TIME:
+      config->maxRetransmitTime = reliability_param;
+      break;
+  }
+  return true;
+}
+
+bool ParseDataChannelOpenAckMessage(const rtc::Buffer& payload) {
+  rtc::ByteBuffer buffer(payload);
+  uint8_t message_type;
+  if (!buffer.ReadUInt8(&message_type)) {
+    LOG(LS_WARNING) << "Could not read OPEN_ACK message type.";
+    return false;
+  }
+  if (message_type != DATA_CHANNEL_OPEN_ACK_MESSAGE_TYPE) {
+    LOG(LS_WARNING) << "Data Channel OPEN_ACK message of unexpected type: "
+                    << message_type;
+    return false;
+  }
+  return true;
+}
+
+bool WriteDataChannelOpenMessage(const std::string& label,
+                                 const DataChannelInit& config,
+                                 rtc::Buffer* payload) {
+  // Format defined at
+  // http://tools.ietf.org/html/draft-ietf-rtcweb-data-protocol-00#section-6.1
+  uint8_t channel_type = 0;
+  uint32_t reliability_param = 0;
+  uint16_t priority = 0;
+  if (config.ordered) {
+    if (config.maxRetransmits > -1) {
+      channel_type = DCOMCT_ORDERED_PARTIAL_RTXS;
+      reliability_param = config.maxRetransmits;
+    } else if (config.maxRetransmitTime > -1) {
+      channel_type = DCOMCT_ORDERED_PARTIAL_TIME;
+      reliability_param = config.maxRetransmitTime;
+    } else {
+      channel_type = DCOMCT_ORDERED_RELIABLE;
+    }
+  } else {
+    if (config.maxRetransmits > -1) {
+      channel_type = DCOMCT_UNORDERED_PARTIAL_RTXS;
+      reliability_param = config.maxRetransmits;
+    } else if (config.maxRetransmitTime > -1) {
+      channel_type = DCOMCT_UNORDERED_PARTIAL_TIME;
+      reliability_param = config.maxRetransmitTime;
+    } else {
+      channel_type = DCOMCT_UNORDERED_RELIABLE;
+    }
+  }
+
+  rtc::ByteBuffer buffer(
+      NULL, 20 + label.length() + config.protocol.length(),
+      rtc::ByteBuffer::ORDER_NETWORK);
+  buffer.WriteUInt8(DATA_CHANNEL_OPEN_MESSAGE_TYPE);
+  buffer.WriteUInt8(channel_type);
+  buffer.WriteUInt16(priority);
+  buffer.WriteUInt32(reliability_param);
+  buffer.WriteUInt16(static_cast<uint16_t>(label.length()));
+  buffer.WriteUInt16(static_cast<uint16_t>(config.protocol.length()));
+  buffer.WriteString(label);
+  buffer.WriteString(config.protocol);
+  payload->SetData(buffer.Data(), buffer.Length());
+  return true;
+}
+
+void WriteDataChannelOpenAckMessage(rtc::Buffer* payload) {
+  rtc::ByteBuffer buffer(rtc::ByteBuffer::ORDER_NETWORK);
+  buffer.WriteUInt8(DATA_CHANNEL_OPEN_ACK_MESSAGE_TYPE);
+  payload->SetData(buffer.Data(), buffer.Length());
+}
+}  // namespace webrtc