Add `IApplication::getInstance()`

The existence of `IApplication::getInstance()` was required by the consumer code but not mandated by the interface. In practice, `getInstance()` exists as `AbstractApplication` extends `SingletonFactory`.

Close #3823

diff --git a/wcfsetup/install/files/lib/system/application/IApplication.class.php b/wcfsetup/install/files/lib/system/application/IApplication.class.php
index d73b34f491de3d15ed4fef968dc8784359a26cde..0dd3d8b68a1314b36d364183a2922b3d369e8eb6 100644 (file)
--- a/wcfsetup/install/files/lib/system/application/IApplication.class.php
+++ b/wcfsetup/install/files/lib/system/application/IApplication.class.php
@@ -2,6 +2,8 @@
 
 namespace wcf\system\application;
 
+use wcf\system\SingletonFactory;
+
 /**
  * Default interface for all applications for the WoltLab Suite.
  *
@@ -47,6 +49,11 @@ interface IApplication
      */
     public function getPrimaryController();
 
+    /**
+     * @see SingletonFactory::getInstance()
+     */
+    public static function getInstance();
+
     /**
      * Forwards unknown method calls to WCF.
      *