Fix generated avatar in message notification
My avatar is yellow, but in the notification it was some blue one.
I assume it still uses the username when it should use the user ID.
Make sure that for IRC users it still uses the username.

diff --git a/src/main/java/com/faforever/client/chat/AbstractChatTabController.java b/src/main/java/com/faforever/client/chat/AbstractChatTabController.java
index d63ea7d2..f0cb7f46 100644
--- a/src/main/java/com/faforever/client/chat/AbstractChatTabController.java
+++ b/src/main/java/com/faforever/client/chat/AbstractChatTabController.java
@@ -693,18 +693,23 @@ public abstract class AbstractChatTabController {
   }
 
   protected void showNotificationIfNecessary(ChatMessage chatMessage) {
-    if (!stage.isFocused() || !stage.isShowing()) {
-      notificationService.addNotification(new TransientNotification(
-          chatMessage.getUsername(),
-          chatMessage.getMessage(),
-          IdenticonUtil.createIdenticon(chatMessage.getUsername()),
-          new Action(event -> {
-            mainController.selectChatTab();
-            stage.toFront();
-            getRoot().getTabPane().getSelectionModel().select(getRoot());
-          }))
-      );
+    if (stage.isFocused() && stage.isShowing()) {
+      return;
     }
+
+    PlayerInfoBean player = playerService.getPlayerForUsername(chatMessage.getUsername());
+    String identiconSource = player != null ? String.valueOf(player.getId()) : chatMessage.getUsername();
+
+    notificationService.addNotification(new TransientNotification(
+        chatMessage.getUsername(),
+        chatMessage.getMessage(),
+        IdenticonUtil.createIdenticon(identiconSource),
+        new Action(event -> {
+          mainController.selectChatTab();
+          stage.toFront();
+          getRoot().getTabPane().getSelectionModel().select(getRoot());
+        }))
+    );
   }
 
   protected String getMessageCssClass(String login) {
['src/main/java/com/faforever/client/chat/AbstractChatTabController.java']