Fix the bug that call to a member function getFrameFilters() on null

src/Whoops/Handler/PrettyPageHandler.php

@@ -287,6 +287,7 @@ class PrettyPageHandler extends Handler
         $vars["tables"] = array_merge($extraTables, $vars["tables"]);
 
         $plainTextHandler = new PlainTextHandler();
+        $plainTextHandler->setRun($this->getRun());
         $plainTextHandler->setException($this->getException());
         $plainTextHandler->setInspector($this->getInspector());
         $vars["preface"] = "<!--\n\n\n" .  $this->templateHelper->escape($plainTextHandler->generateResponse()) . "\n\n\n\n\n\n\n\n\n\n\n-->";
@@ -753,7 +754,7 @@ class PrettyPageHandler extends Handler
 
     /**
      * Set the application paths.
-     * 
+     *
      * @return void
      */
     public function setApplicationPaths(array $applicationPaths)