diff --git a/core/lib/Drupal/Core/Extension/ModuleHandler.php b/core/lib/Drupal/Core/Extension/ModuleHandler.php
index 8a1abb4..02d80ad 100644
--- a/core/lib/Drupal/Core/Extension/ModuleHandler.php
+++ b/core/lib/Drupal/Core/Extension/ModuleHandler.php
@@ -264,7 +264,7 @@ public function implementsHook($module, $hook) {
   /**
    * Implements \Drupal\Core\Extension\ModuleHandlerInterface::invoke().
    */
-  public function invoke($module, $hook, $args = array()) {
+  public function invoke($module, $hook, array $args = array()) {
     if (!$this->implementsHook($module, $hook)) {
       return;
     }
@@ -275,7 +275,7 @@ public function invoke($module, $hook, $args = array()) {
   /**
    * Implements \Drupal\Core\Extension\ModuleHandlerInterface::invokeAll().
    */
-  public function invokeAll($hook, $args = array()) {
+  public function invokeAll($hook, array $args = array()) {
     $return = array();
     $implementations = $this->getImplementations($hook);
     foreach ($implementations as $module) {
diff --git a/core/lib/Drupal/Core/Extension/ModuleHandlerInterface.php b/core/lib/Drupal/Core/Extension/ModuleHandlerInterface.php
index 9540391..a74f9cd 100644
--- a/core/lib/Drupal/Core/Extension/ModuleHandlerInterface.php
+++ b/core/lib/Drupal/Core/Extension/ModuleHandlerInterface.php
@@ -185,7 +185,7 @@ public function implementsHook($module, $hook);
    * @return mixed
    *   The return value of the hook implementation.
    */
-  public function invoke($module, $hook, $args = array());
+  public function invoke($module, $hook, array $args = array());
 
   /**
    * Invokes a hook in all enabled modules that implement it.
@@ -199,7 +199,7 @@ public function invoke($module, $hook, $args = array());
    *   An array of return values of the hook implementations. If modules return
    *   arrays from their implementations, those are merged into one array.
    */
-  public function invokeAll($hook, $args = array());
+  public function invokeAll($hook, array $args = array());
 
   /**
    * Passes alterable variables to specific hook_TYPE_alter() implementations.