Update to Random_Compat 1.0.9.

This update includes fixes for Windows support & libSodium support, and removes the `Throwable` Polyfill due to PHP7 incompatibilities. 

Fixes #28633


git-svn-id: https://develop.svn.wordpress.org/trunk@35365 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/random_compat/error_polyfill.php

@@ -26,15 +26,9 @@
  * SOFTWARE.
  */
 
-if (!interface_exists('Throwable', false)) {
-    interface Throwable
-    {
-    }
-}
-
 if (!class_exists('Error', false)) {
     // We can't really avoid making this extend Exception in PHP 5.
-    class Error extends Exception implements Throwable
+    class Error extends Exception
     {
         
     }