code: private Observable<Boolean> upsertTempMessage(ChatMessage message) {
          return persistenceController.updateStoreWithNewMessage(message, noConversationListener)
                  .doOnError(t -> log.e("Error saving temp message " + t.getLocalizedMessage()))
                  .onErrorReturn(t -> false);
      }
docs: Insert temporary message to the store for the ui to be responsive.
  
  @param message Message to be send.
  @return Observable emitting result of operations.