refactor: is_probably_private_reply: Remove reaction-specific code

Instead, look up the 1:1 chat in `receive_imf::add_parts()`. This is a more generic approach to fix
assigning outgoing reactions to 1:1 chats in the multi-device setup. Although currently both
approaches give the same result, this way we can even implement a "react privately"
functionality. Maybe it sounds useless, but it seems better to have less reaction-specific code.

src/receive_imf/tests.rs

@@ -9,7 +9,7 @@ use crate::chat::{
     ChatVisibility,
 };
 use crate::chatlist::Chatlist;
-use crate::constants::{DC_GCL_FOR_FORWARDING, DC_GCL_NO_SPECIALS};
+use crate::constants::{ShowEmails, DC_GCL_FOR_FORWARDING, DC_GCL_NO_SPECIALS};
 use crate::download::MIN_DOWNLOAD_LIMIT;
 use crate::imap::prefetch_should_download;
 use crate::imex::{imex, ImexMode};
@@ -142,6 +142,35 @@ async fn test_adhoc_group_show_accepted_contact_unknown() {
     assert_eq!(chats.len(), 0);
 }
 
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn test_adhoc_group_outgoing_show_accepted_contact_unaccepted() -> Result<()> {
+    let mut tcm = TestContextManager::new();
+    let alice = &tcm.alice().await;
+    let bob = &tcm.bob().await;
+    bob.set_config(
+        Config::ShowEmails,
+        Some(&ShowEmails::AcceptedContacts.to_string()),
+    )
+    .await?;
+    tcm.send_recv(alice, bob, "hi").await;
+    receive_imf(
+        bob,
+        b"From: bob@example.net\n\
+        To: alice@example.org, claire@example.com\n\
+        Message-ID: <3333@example.net>\n\
+        Date: Sun, 22 Mar 2020 22:37:57 +0000\n\
+        \n\
+        hello\n",
+        false,
+    )
+    .await?;
+    let chats = Chatlist::try_load(bob, 0, None, None).await?;
+    assert_eq!(chats.len(), 1);
+    let chat_id = chats.get_chat_id(0)?;
+    assert_eq!(chat_id.get_msg_cnt(bob).await?, 1);
+    Ok(())
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn test_adhoc_group_show_accepted_contact_known() {
     let t = TestContext::new_alice().await;