Reland of tracing v2: Introduce TraceBufferWriter (https://codereview.chromium.org/2196663002)

components/tracing/core/proto_zero_message.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.
 
 #include "components/tracing/core/proto_zero_message.h"
 
 #include <string.h>
 
 #include "components/tracing/core/proto_zero_message_handle.h"
 
@@ skipping 64 matching lines @@
     EndNestedMessage();
 
   if (size_field_.is_valid()) {
 // Write the length of the nested message a posteriori, using a leading-zero
 // redundant varint encoding.
 #if DCHECK_IS_ON()
     DCHECK(!sealed_);
 #endif
     DCHECK_LT(size_, proto::kMaxMessageLength);
     DCHECK_EQ(proto::kMessageLengthFieldSize, size_field_.size());
-    proto::WriteRedundantLength(
+    proto::WriteRedundantVarInt(
         static_cast<uint32_t>(size_ - size_already_written_),
         size_field_.begin);
     size_field_.reset();
   }
 
 #if DCHECK_IS_ON()
   sealed_ = true;
   if (handle_)
     handle_->reset_message();
 #endif
@@ skipping 24 matching lines @@
   nested_message_ = message;
 }
 
 void ProtoZeroMessage::EndNestedMessage() {
   size_ += nested_message_->Finalize();
   nested_message_ = nullptr;
 }
 
 }  // namespace v2
 }  // namespace tracing