Update from https://crrev.com/309415

net/spdy/spdy_framer.cc

 // Copyright (c) 2012 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/spdy/spdy_framer.h"
 
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/stats_counters.h"
 #include "base/third_party/valgrind/memcheck.h"
@@ skipping 2850 matching lines @@
   builder.WriteUInt8(static_cast<uint8>(altsvc.protocol_id().length()));
   builder.WriteBytes(altsvc.protocol_id().data(),
                      altsvc.protocol_id().length());
   builder.WriteUInt8(static_cast<uint8>(altsvc.host().length()));
   builder.WriteBytes(altsvc.host().data(), altsvc.host().length());
   builder.WriteBytes(altsvc.origin().data(), altsvc.origin().length());
   DCHECK_LT(GetAltSvcMinimumSize(), builder.length());
   return builder.take();
 }
 
-SpdyFrame* SpdyFramer::SerializePriority(const SpdyPriorityIR& priority) {
+SpdyFrame* SpdyFramer::SerializePriority(const SpdyPriorityIR& priority) const {
   DCHECK_LT(SPDY3, protocol_version());
   size_t size = GetPrioritySize();
 
   SpdyFrameBuilder builder(size, protocol_version());
   builder.BeginNewFrame(*this, PRIORITY, kNoFlags, priority.stream_id());
 
   // Make sure the highest-order bit in the parent stream id is zeroed out.
   uint32 parent_stream_id = priority.parent_stream_id() & 0x7fffffff;
   uint32 exclusive = priority.exclusive() ? 0x80000000 : 0;
   // Set the one-bit exclusivity flag.
@@ skipping 409 matching lines @@
   builder->Seek(compressed_size);
   builder->RewriteLength(*this);
 
   pre_compress_bytes.Add(uncompressed_len);
   post_compress_bytes.Add(compressed_size);
 
   compressed_frames.Increment();
 }
 
 }  // namespace net