FIX: Check for user presence before granting badge (#11745)

app/services/badge_granter.rb

@@ -45,6 +45,7 @@ class BadgeGranter
   def grant
     return if @granted_by && !Guardian.new(@granted_by).can_grant_badges?(@user)
     return unless @badge.present? && @badge.enabled?
+    return if @user.blank?
     return if @badge.badge_grouping_id == BadgeGrouping::GettingStarted && @badge.id != Badge::NewUserOfTheMonth && @user.user_option.skip_new_user_tips
 
     find_by = { badge_id: @badge.id, user_id: @user.id }

spec/services/badge_granter_spec.rb

@@ -280,6 +280,11 @@ describe BadgeGranter do
       expect(user.notifications.find_by(notification_type: Notification.types[:granted_badge]).data_hash["badge_id"]).to eq(badge.id)
     end
 
+    it 'does not fail when user is missing' do
+      BadgeGranter.grant(badge, nil)
+      expect(badge.reload.grant_count).to eq(0)
+    end
+
   end
 
   describe 'revoke' do