Reland of Move tracing namespace from base::debug to base::trace_event.

base/trace_event/trace_event_argument.cc

 // Copyright (c) 2014 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 "base/trace_event/trace_event_argument.h"
 
 #include "base/json/json_writer.h"
 #include "base/values.h"
 
 namespace base {
-namespace debug {
+namespace trace_event {
 
 TracedValue::TracedValue() : root_(new DictionaryValue()) {
   stack_.push_back(root_.get());
 }
 
 TracedValue::~TracedValue() {
   DCHECK_EQ(1u, stack_.size());
 }
 
 void TracedValue::SetInteger(const char* name, int value) {
@@ skipping 84 matching lines @@
   return list;
 }
 
 void TracedValue::AppendAsTraceFormat(std::string* out) const {
   std::string tmp;
   JSONWriter::Write(stack_.front(), &tmp);
   *out += tmp;
   DCHECK_EQ(1u, stack_.size()) << tmp;
 }
 
-}  // namespace debug
+}  // namespace trace_event
 }  // namespace base