Allow staff members to enable safe mode, even if disabled

app/controllers/application_controller.rb

@@ -299,7 +299,7 @@ class ApplicationController < ActionController::Base
   SAFE_MODE = "safe_mode"
 
   def resolve_safe_mode
-    return unless SiteSetting.enable_safe_mode?
+    return unless guardian.can_enable_safe_mode?
 
     safe_mode = params[SAFE_MODE]
     if safe_mode

app/controllers/safe_mode_controller.rb

@@ -24,7 +24,7 @@ class SafeModeController < ApplicationController
   protected
 
   def ensure_safe_mode_enabled
-    raise Discourse::NotFound unless SiteSetting.enable_safe_mode?
+    raise Discourse::NotFound unless guardian.can_enable_safe_mode?
   end
 
 end