smartlist: show last interaction when syncing after importing account

When a new conversation is detected via conversationReady, load the last
messages to show it in the smartlist. Also, in smartlistviewholder,
update last interaction's visibility when needed.

Change-Id: I917e907edcb17d67dce351c2d4da741ffbe51552
GitLab: #859

ring-android/app/src/main/java/cx/ring/viewholders/SmartListViewHolder.java

@@ -83,8 +83,10 @@ public class SmartListViewHolder extends RecyclerView.ViewHolder {
 
             binding.convLastTime.setText(lastInteractionStr);
             if (smartListViewModel.hasOngoingCall()) {
+                binding.convLastItem.setVisibility(View.VISIBLE);
                 binding.convLastItem.setText(itemView.getContext().getString(R.string.ongoing_call));
             } else if (smartListViewModel.getLastEvent() != null) {
+                binding.convLastItem.setVisibility(View.VISIBLE);
                 binding.convLastItem.setText(getLastEventSummary(smartListViewModel.getLastEvent(), itemView.getContext()));
             } else {
                 binding.convLastItem.setVisibility(View.GONE);

ring-android/libringclient/src/main/java/net/jami/services/AccountService.java

@@ -1639,6 +1639,7 @@ public class AccountService {
             }
         }
         account.conversationStarted(conversation);
+        loadMore(conversation, 2);
     }
 
     public void conversationRemoved(String accountId, String conversationId) {