Split up quic_frames.{h,cc} into files for each frame type.

net/quic/core/frames/quic_padding_frame.cc

Index: net/quic/core/frames/quic_padding_frame.cc
diff --git a/net/quic/core/frames/quic_padding_frame.cc b/net/quic/core/frames/quic_padding_frame.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0f15af1f51e6782a68e6a78ac87885bb5ddfa324
--- /dev/null
+++ b/net/quic/core/frames/quic_padding_frame.cc
@@ -0,0 +1,17 @@
+// Copyright (c) 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/quic/core/frames/quic_padding_frame.h"
+
+using std::ostream;
+using std::string;
+
+namespace net {
+
+ostream& operator<<(ostream& os, const QuicPaddingFrame& padding_frame) {
+  os << "{ num_padding_bytes: " << padding_frame.num_padding_bytes << " }\n";
+  return os;
+}
+
+}  // namespace net