Add new HTTP/2 and HPACK decoder in net/http2/.

net/http2/decoder/payload_decoders/priority_payload_decoder.cc

Index: net/http2/decoder/payload_decoders/priority_payload_decoder.cc
diff --git a/net/http2/decoder/payload_decoders/priority_payload_decoder.cc b/net/http2/decoder/payload_decoders/priority_payload_decoder.cc
new file mode 100644
index 0000000000000000000000000000000000000000..51ae80b9808c4be0dba7144851db3ae386f494d3
--- /dev/null
+++ b/net/http2/decoder/payload_decoders/priority_payload_decoder.cc
@@ -0,0 +1,64 @@
+// Copyright 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/http2/decoder/payload_decoders/priority_payload_decoder.h"
+
+#include "base/logging.h"
+#include "net/http2/decoder/decode_buffer.h"
+#include "net/http2/decoder/http2_frame_decoder_listener.h"
+#include "net/http2/http2_constants.h"
+#include "net/http2/http2_structures.h"
+
+namespace net {
+
+DecodeStatus PriorityPayloadDecoder::StartDecodingPayload(
+    FrameDecoderState* state,
+    DecodeBuffer* db) {
+  DVLOG(2) << "PriorityPayloadDecoder::StartDecodingPayload: "
+           << state->frame_header();
+  DCHECK_EQ(Http2FrameType::PRIORITY, state->frame_header().type);
+  DCHECK_LE(db->Remaining(), state->frame_header().payload_length);
+  // PRIORITY frames have no flags.
+  DCHECK_EQ(0, state->frame_header().flags);
+  state->InitializeRemainders();
+  return HandleStatus(
+      state, state->StartDecodingStructureInPayload(&priority_fields_, db));
+}
+
+DecodeStatus PriorityPayloadDecoder::ResumeDecodingPayload(
+    FrameDecoderState* state,
+    DecodeBuffer* db) {
+  DVLOG(2) << "PriorityPayloadDecoder::ResumeDecodingPayload"
+           << "  remaining_payload=" << state->remaining_payload()
+           << "  db->Remaining=" << db->Remaining();
+  DCHECK_EQ(Http2FrameType::PRIORITY, state->frame_header().type);
+  DCHECK_LE(db->Remaining(), state->frame_header().payload_length);
+  return HandleStatus(
+      state, state->ResumeDecodingStructureInPayload(&priority_fields_, db));
+}
+
+DecodeStatus PriorityPayloadDecoder::HandleStatus(FrameDecoderState* state,
+                                                  DecodeStatus status) {
+  if (status == DecodeStatus::kDecodeDone) {
+    if (state->remaining_payload() == 0) {
+      state->listener()->OnPriorityFrame(state->frame_header(),
+                                         priority_fields_);
+      return DecodeStatus::kDecodeDone;
+    }
+    // Payload is too long.
+    return state->ReportFrameSizeError();
+  }
+  // Not done decoding the structure. Either we've got more payload to decode,
+  // or we've run out because the payload is too short, in which case
+  // OnFrameSizeError will have already been called.
+  DCHECK(
+      (status == DecodeStatus::kDecodeInProgress &&
+       state->remaining_payload() > 0) ||
+      (status == DecodeStatus::kDecodeError && state->remaining_payload() == 0))
+      << "\n status=" << status
+      << "; remaining_payload=" << state->remaining_payload();
+  return status;
+}
+
+}  // namespace net