Reland r145993.

sync/api/sync_change.cc

Index: sync/api/sync_change.cc
diff --git a/sync/api/sync_change.cc b/sync/api/sync_change.cc
index 64da5b797dcbe11d1c38f62d9ab26ce5aaa8ba17..ee1cdeafd6ed80c7bed307b9353956be4bd1e1fd 100644
--- a/sync/api/sync_change.cc
+++ b/sync/api/sync_change.cc
@@ -11,8 +11,12 @@ namespace syncer {
 SyncChange::SyncChange() : change_type_(ACTION_INVALID) {
 }
 
-SyncChange::SyncChange(SyncChangeType change_type, const SyncData& sync_data)
-    : change_type_(change_type),
+SyncChange::SyncChange(
+    const tracked_objects::Location& from_here,
+    SyncChangeType change_type,
+    const SyncData& sync_data)
+    : location_(from_here),
+      change_type_(change_type),
       sync_data_(sync_data) {
   DCHECK(IsValid());
 }
@@ -66,8 +70,9 @@ std::string SyncChange::ChangeTypeToString(SyncChangeType change_type) {
 }
 
 std::string SyncChange::ToString() const {
-  return "{ changeType: " + ChangeTypeToString(change_type_) +
-      ", syncData: " + sync_data_.ToString() + "}";
+  return "{ " + location_.ToString() + ", changeType: " +
+      ChangeTypeToString(change_type_) + ", syncData: " +
+      sync_data_.ToString() + "}";
 }
 
 void PrintTo(const SyncChange& sync_change, std::ostream* os) {