Add dvlog_always_on to enable DVLOG without DEBUG and DCHECK option

net/spdy/core/hpack/hpack_huffman_decoder.cc

 // 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.
 //
 // Decoder for strings encoded using the HPACK Huffman Code (see
 // https://httpwg.github.io/specs/rfc7541.html#huffman.code).
 //
 // This implementation is inspired by the One-Shift algorithm described in
 // "On the Implementation of Minimum Redundancy Prefix Codes", by Alistair
 // Moffat and Andrew Turpin, 1997.
@@ skipping 140 matching lines @@
     0xee, 0xf0, 0xf2, 0xf3, 0xff, 0xcb, 0xcc, 0xd3,
     0xd4, 0xd6, 0xdd, 0xde, 0xdf, 0xf1, 0xf4, 0xf5,
     0xf6, 0xf7, 0xf8, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe,
     0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x0b,
     0x0c, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14,
     0x15, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d,
     0x1e, 0x1f, 0x7f, 0xdc, 0xf9, 0x0a, 0x0d, 0x16,
 };
 // clang-format on
 
-#if DCHECK_IS_ON()
+#if DCHECK_IS_ON() || DVLOG_IS_ON()
 
 // Only used in DLOG.
 bool IsEOSPrefix(HuffmanWord bits, HuffmanCodeLength bits_available) {
   if (bits_available == 0) {
     return true;
   }
   // We expect all the bits below the high order |bits_available| bits
   // to be cleared.
   HuffmanWord expected = HuffmanWord(0xffffffff) << (32 - bits_available);
   return bits == expected;
 }
 
-#endif  // DCHECK_IS_ON()
+#endif  // DCHECK_IS_ON() || DVLOG_IS_ON()
 
 }  // namespace
 
 // TODO(jamessynge): Should we read these magic numbers from
 // kLengthToFirstLJCode? Would that reduce cache consumption? Slow decoding?
 // TODO(jamessynge): Is this being inlined by the compiler? Should we inline
 // into DecodeString the tests for code lengths 5 through 8 (> 99% of codes
 // according to the HPACK spec)?
 HpackHuffmanDecoder::HuffmanCodeLength HpackHuffmanDecoder::CodeLengthOfPrefix(
     HpackHuffmanDecoder::HuffmanWord value) {
@@ skipping 206 matching lines @@
       // Get some more bits for decoding (up to 8). |peeked_success| is true
       // if we got any bits.
       peeked_success = in->PeekBits(&bits_available, &bits);
     }
     DLOG_IF(WARNING, (VLOG_IS_ON(2) && bits_available < 32 && !peeked_success))
         << "no more peeking possible";
   }
 }
 
 }  // namespace net