Adds compileReadonly function (#42717)

Author: mahmoudmohamedramadan

src/Illuminate/View/Compilers/Concerns/CompilesConditionals.php

@@ -337,4 +337,15 @@ protected function compileDisabled($condition)
     {
         return "<?php if{$condition}: echo 'disabled'; endif; ?>";
     }
+
+    /**
+     * Compile a readonly block into valid PHP.
+     *
+     * @param  string  $condition
+     * @return string
+     */
+    protected function compileReadonly($condition)
+    {
+        return "<?php if{$condition}: echo 'readonly'; endif; ?>";
+    }
 }