Revert "[11.x] Declare bindings and singletons properties in Service Provider…" (#52288)

This reverts commit ed28a45.

Author: driesvints

src/Illuminate/Foundation/Application.php

@@ -870,14 +870,18 @@ public function register($provider, $force = false)
         // If there are bindings / singletons set as properties on the provider we
         // will spin through them and register them with the application, which
         // serves as a convenience layer while registering a lot of bindings.
-        foreach ($provider->bindings as $key => $value) {
-            $this->bind($key, $value);
+        if (property_exists($provider, 'bindings')) {
+            foreach ($provider->bindings as $key => $value) {
+                $this->bind($key, $value);
+            }
         }
 
-        foreach ($provider->singletons as $key => $value) {
-            $key = is_int($key) ? $value : $key;
+        if (property_exists($provider, 'singletons')) {
+            foreach ($provider->singletons as $key => $value) {
+                $key = is_int($key) ? $value : $key;
 
-            $this->singleton($key, $value);
+                $this->singleton($key, $value);
+            }
         }
 
         $this->markAsRegistered($provider);

src/Illuminate/Support/ServiceProvider.php

@@ -19,20 +19,6 @@ abstract class ServiceProvider
      */
     protected $app;
 
-    /**
-     * All of the container bindings that should be registered.
-     *
-     * @var array
-     */
-    public $bindings = [];
-
-    /**
-     * All of the singletons that should be registered.
-     *
-     * @var array
-     */
-    public $singletons = [];
-
     /**
      * All of the registered booting callbacks.
      *