Replace FOR_EACH_OBSERVER in components/drive with range-based for

components/drive/service/fake_drive_service.cc

Index: components/drive/service/fake_drive_service.cc
diff --git a/components/drive/service/fake_drive_service.cc b/components/drive/service/fake_drive_service.cc
index ad0d1f66efdfc479dc6e6756ffad86cf6ffa7f74..60f84c56e35b7a4a4a0d0bc0ade5a0a4bc63169d 100644
--- a/components/drive/service/fake_drive_service.cc
+++ b/components/drive/service/fake_drive_service.cc
@@ -1793,7 +1793,8 @@ FakeDriveService::StartBatchRequest() {
 }
 
 void FakeDriveService::NotifyObservers() {
-  FOR_EACH_OBSERVER(ChangeObserver, change_observers_, OnNewChangeAvailable());
+  for (auto& observer : change_observers_)
+    observer.OnNewChangeAvailable();
 }
 
 }  // namespace drive