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

net/http2/hpack/http2_hpack_constants.h

-// 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.
-
-#ifndef NET_HTTP2_HPACK_HTTP2_HPACK_CONSTANTS_H_
-#define NET_HTTP2_HPACK_HTTP2_HPACK_CONSTANTS_H_
-
-// Enum HpackEntryType identifies the 5 basic types of HPACK Block Entries.
-//
-// See the spec for details:
-// https://http2.github.io/http2-spec/compression.html#rfc.section.6
-
-#include <ostream>
-#include <string>
-
-#include "net/base/net_export.h"
-
-namespace net {
-
-enum class HpackEntryType {
-  // Entry is an index into the static or dynamic table. Decoding it has no
-  // effect on the dynamic table.
-  kIndexedHeader,
-
-  // The entry contains a literal value. The name may be either a literal or a
-  // reference to an entry in the static or dynamic table.
-  // The entry is added to the dynamic table after decoding.
-  kIndexedLiteralHeader,
-
-  // The entry contains a literal value. The name may be either a literal or a
-  // reference to an entry in the static or dynamic table.
-  // The entry is not added to the dynamic table after decoding, but a proxy
-  // may choose to insert the entry into its dynamic table when forwarding
-  // to another endpoint.
-  kUnindexedLiteralHeader,
-
-  // The entry contains a literal value. The name may be either a literal or a
-  // reference to an entry in the static or dynamic table.
-  // The entry is not added to the dynamic table after decoding, and a proxy
-  // must NOT insert the entry into its dynamic table when forwarding to another
-  // endpoint.
-  kNeverIndexedLiteralHeader,
-
-  // Entry conveys the size limit of the dynamic table of the encoder to
-  // the decoder. May be used to flush the table by sending a zero and then
-  // resetting the size back up to the maximum that the encoder will use
-  // (within the limits of SETTINGS_HEADER_TABLE_SIZE sent by the
-  // decoder to the encoder, with the default of 4096 assumed).
-  kDynamicTableSizeUpdate,
-};
-
-// Returns the name of the enum member.
-NET_EXPORT_PRIVATE std::string HpackEntryTypeToString(HpackEntryType v);
-
-// Inserts the name of the enum member into |out|.
-NET_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& out,
-                                            HpackEntryType v);
-
-}  // namespace net
-
-#endif  // NET_HTTP2_HPACK_HTTP2_HPACK_CONSTANTS_H_