add device messages about removed oauth2, resulting in non-working gm…

…ail logins

src/main/java/org/thoughtcrime/securesms/ConversationListActivity.java

@@ -18,6 +18,7 @@
 
 import static org.thoughtcrime.securesms.ConversationActivity.CHAT_ID_EXTRA;
 import static org.thoughtcrime.securesms.ConversationActivity.STARTING_POSITION_EXTRA;
+import static org.thoughtcrime.securesms.connect.DcHelper.CONFIG_SERVER_FLAGS;
 import static org.thoughtcrime.securesms.util.RelayUtil.acquireRelayMessageContent;
 import static org.thoughtcrime.securesms.util.RelayUtil.getDirectSharingChatId;
 import static org.thoughtcrime.securesms.util.RelayUtil.getSharedTitle;
@@ -141,6 +142,21 @@ protected void onCreate(Bundle icicle, boolean ready) {
       }
       // /add info
 
+
+      // add info about how to exit gmail's oauth2.
+      // we add the info just by checking DC_LP_AUTH_OAUTH2,
+      // as there are eg. custom domains and we do not have the information "is-google" in the frontend,
+      // and it is not worth trying to get that, majority of oauth2 is google.
+      // also, we cannot really test this.
+      // (there may be false positive in case of yandex, but that is probably an even smaller number)
+      final int serverFlags = dcContext.getConfigInt(CONFIG_SERVER_FLAGS);
+      if ((serverFlags & DcContext.DC_LP_AUTH_OAUTH2)!=0) {
+        DcMsg msg = new DcMsg(dcContext, DcMsg.DC_MSG_TEXT);
+        msg.setText("⚠️ GMail Users: If you have problems using GMail, go to \"Settings / Advanced / Password and Account\" and login again using an \"App Password\".\n\nThe login will show more hints.");
+        dcContext.addDeviceMsg("info_about_gmail_oauth2_removal4", msg);
+      }
+      // /add info
+
     } catch(Exception e) {
       e.printStackTrace();
     }