sync: Introduce classes for per-type counters

sync/internal_api/public/sessions/commit_counters.cc

+// Copyright 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 "sync/internal_api/public/sessions/commit_counters.h"
+
+#include "base/json/json_string_value_serializer.h"
+#include "base/values.h"
+
+namespace syncer {
+
+CommitCounters::CommitCounters()
+  : num_commits_attempted(0),
+    num_commits_success(0),
+    num_commits_conflict(0),
+    num_commits_error(0) {}
+
+CommitCounters::~CommitCounters() {}
+
+scoped_ptr<base::DictionaryValue> CommitCounters::ToValue() const {
+  scoped_ptr<base::DictionaryValue> value(new base::DictionaryValue());
+  value->SetInteger("numCommitsAttempted", num_commits_attempted);
+  value->SetInteger("numCommitsSuccess", num_commits_success);
+  value->SetInteger("numCommitsConflict", num_commits_conflict);
+  value->SetInteger("numCommitsError", num_commits_error);
+  return value.Pass();
+}
+
+std::string CommitCounters::ToString() const {
+  std::string result;
+  scoped_ptr<base::DictionaryValue> value = ToValue();
+  JSONStringValueSerializer serializer(&result);
+  serializer.Serialize(*value);
+  return result;
+}
+
+}  // namespace syncer