Address some violations of chromium-style.

webrtc/modules/rtp_rtcp/source/rtp_packet.cc

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 44 matching lines @@
 // |                           Payload                             |
 // |             ....              :  padding...                   |
 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 // |               padding         | Padding size  |
 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 Packet::Packet() : Packet(nullptr, kDefaultPacketSize) {}
 
 Packet::Packet(const ExtensionManager* extensions)
     : Packet(extensions, kDefaultPacketSize) {}
 
+Packet::Packet(const Packet&) = default;
+
 Packet::Packet(const ExtensionManager* extensions, size_t capacity)
     : buffer_(capacity) {
   RTC_DCHECK_GE(capacity, kFixedHeaderSize);
   Clear();
   if (extensions) {
     IdentifyExtensions(*extensions);
   } else {
     for (size_t i = 0; i < kMaxExtensionHeaders; ++i)
       extension_entries_[i].type = ExtensionManager::kInvalidType;
   }
@@ skipping 498 matching lines @@
 uint8_t* Packet::WriteAt(size_t offset) {
   return buffer_.data() + offset;
 }
 
 void Packet::WriteAt(size_t offset, uint8_t byte) {
   buffer_.data()[offset] = byte;
 }
 
 }  // namespace rtp
 }  // namespace webrtc