[BUGFIX] Check if install tool enable file exists before removing it

The is_file() check got lost during the refactoring in
d855b470.

Change-Id: Ia1688099a7ccd32667562e8c7f83fd54bb669f4a
Resolves: #80354
Releases: master, 7.6
Reviewed-on: https://review.typo3.org/52100


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Josef Glatz <josef.glatz@typo3.org>
Tested-by: Josef Glatz <josef.glatz@typo3.org>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>

typo3/sysext/install/Classes/Controller/Action/Step/DefaultConfiguration.php

@@ -133,7 +133,7 @@ For each website you need a TypoScript template on the main page of your website
         );
         $formProtection->clean();
 
-        if (!EnableFileService::isInstallToolEnableFilePermanent()) {
+        if (EnableFileService::installToolEnableFileExists() && !EnableFileService::isInstallToolEnableFilePermanent()) {
             EnableFileService::removeInstallToolEnableFile();
         }
 

typo3/sysext/install/Classes/Controller/ToolController.php

@@ -73,7 +73,7 @@ class ToolController extends AbstractController
     {
         $action = $this->getAction();
         if ($action === 'logout') {
-            if (!EnableFileService::isInstallToolEnableFilePermanent()) {
+            if (EnableFileService::installToolEnableFileExists() && !EnableFileService::isInstallToolEnableFilePermanent()) {
                 EnableFileService::removeInstallToolEnableFile();
             }