[Sync] Remove unneeded 'using syncer::' lines and 'syncer::' scopings

sync/syncable/directory_backing_store.cc

Index: sync/syncable/directory_backing_store.cc
diff --git a/sync/syncable/directory_backing_store.cc b/sync/syncable/directory_backing_store.cc
index 293a4440d029db319daf6e2cdbb419bda6fa48b8..f1bfe8c4190d9a3856bac6be9f20ebe398e75d4e 100644
--- a/sync/syncable/directory_backing_store.cc
+++ b/sync/syncable/directory_backing_store.cc
@@ -51,7 +51,7 @@ void BindFields(const EntryKernel& entry,
   }
   for ( ; i < TIME_FIELDS_END; ++i) {
     statement->BindInt64(index++,
-                         syncer::TimeToProtoTime(
+                         TimeToProtoTime(
                              entry.ref(static_cast<TimeField>(i))));
   }
   for ( ; i < ID_FIELDS_END; ++i) {
@@ -81,7 +81,7 @@ EntryKernel* UnpackEntry(sql::Statement* statement) {
   }
   for ( ; i < TIME_FIELDS_END; ++i) {
     kernel->put(static_cast<TimeField>(i),
-                syncer::ProtoTimeToTime(statement->ColumnInt64(i)));
+                ProtoTimeToTime(statement->ColumnInt64(i)));
   }
   for ( ; i < ID_FIELDS_END; ++i) {
     kernel->mutable_ref(static_cast<IdField>(i)).s_ =
@@ -544,14 +544,14 @@ ModelType DirectoryBackingStore::ModelIdToModelTypeEnum(
     const void* data, int size) {
   sync_pb::EntitySpecifics specifics;
   if (!specifics.ParseFromArray(data, size))
-    return syncer::UNSPECIFIED;
-  return syncer::GetModelTypeFromSpecifics(specifics);
+    return UNSPECIFIED;
+  return GetModelTypeFromSpecifics(specifics);
 }
 
 // static
 string DirectoryBackingStore::ModelTypeEnumToModelId(ModelType model_type) {
   sync_pb::EntitySpecifics specifics;
-  syncer::AddDefaultFieldValue(model_type, &specifics);
+  AddDefaultFieldValue(model_type, &specifics);
   return specifics.SerializeAsString();
 }
 
@@ -997,7 +997,7 @@ bool DirectoryBackingStore::CreateTables() {
 
   {
     // Insert the entry for the root into the metas table.
-    const int64 now = syncer::TimeToProtoTime(base::Time::Now());
+    const int64 now = TimeToProtoTime(base::Time::Now());
     sql::Statement s(db_->GetUniqueStatement(
             "INSERT INTO metas "
             "( id, metahandle, is_dir, ctime, mtime) "