Convert //sync from scoped_ptr to std::unique_ptr

sync/internal_api/public/sessions/update_counters.cc

Index: sync/internal_api/public/sessions/update_counters.cc
diff --git a/sync/internal_api/public/sessions/update_counters.cc b/sync/internal_api/public/sessions/update_counters.cc
index 7f54fcb34dfa76058215368d127c0397bdc7a63b..83b9809bbed102ca0fcf129fb54bc4f42e46a4cc 100644
--- a/sync/internal_api/public/sessions/update_counters.cc
+++ b/sync/internal_api/public/sessions/update_counters.cc
@@ -21,8 +21,8 @@ UpdateCounters::UpdateCounters()
 
 UpdateCounters::~UpdateCounters() {}
 
-scoped_ptr<base::DictionaryValue> UpdateCounters::ToValue() const {
-  scoped_ptr<base::DictionaryValue> value(new base::DictionaryValue());
+std::unique_ptr<base::DictionaryValue> UpdateCounters::ToValue() const {
+  std::unique_ptr<base::DictionaryValue> value(new base::DictionaryValue());
 
   value->SetInteger("numUpdatesReceived", num_updates_received);
   value->SetInteger("numReflectedUpdatesReceived",
@@ -44,7 +44,7 @@ scoped_ptr<base::DictionaryValue> UpdateCounters::ToValue() const {
 
 std::string UpdateCounters::ToString() const {
   std::string result;
-  scoped_ptr<base::DictionaryValue> value = ToValue();
+  std::unique_ptr<base::DictionaryValue> value = ToValue();
   JSONStringValueSerializer serializer(&result);
   serializer.Serialize(*value);
   return result;