[BUGFIX] Prevent PHP type error and stale language cache

PHP is raising an error if $pageId cannot be resolved to an
integer value as required by method signature.

Additionally, an internally cached array is built based on a
dynamic value but the internal cache is not keyed by this
value or flushed when the value changes.

This patch:

* Casts an unresolved page ID to integer zero.
* Removes the internal cache of languages since the array
  now depends entirely on a unique input value, $pageId.

Resolves: #89692
Resolves: #90073
Releases: master, 9.5
Change-Id: I3d74b4c7575375aae23a7e2473100104c4700966
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/62974
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Alexander Schnitzler <git@alexanderschnitzler.de>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Frank Nägler <frank.naegler@typo3.org>
Reviewed-by: Alexander Schnitzler <git@alexanderschnitzler.de>
Reviewed-by: Benni Mack <benni@typo3.org>

typo3/sysext/workspaces/Classes/Service/GridDataService.php

@@ -79,11 +79,6 @@ class GridDataService implements LoggerAwareInterface
      */
     protected $workspacesCache;
 
-    /**
-     * @var array
-     */
-    protected $systemLanguages;
-
     /**
      * @var IntegrityService
      */
@@ -598,7 +593,7 @@ protected function getLanguageValue($table, array $record)
     protected function getSystemLanguageValue($id, $pageId, $key)
     {
         $value = null;
-        $systemLanguages = $this->getSystemLanguages($pageId);
+        $systemLanguages = $this->getSystemLanguages((int)$pageId);
         if (!empty($systemLanguages[$id][$key])) {
             $value = $systemLanguages[$id][$key];
         }
@@ -613,11 +608,7 @@ protected function getSystemLanguageValue($id, $pageId, $key)
      */
     public function getSystemLanguages(int $pageId)
     {
-        if (!isset($this->systemLanguages)) {
-            $translateTools = GeneralUtility::makeInstance(TranslationConfigurationProvider::class);
-            $this->systemLanguages = $translateTools->getSystemLanguages($pageId);
-        }
-        return $this->systemLanguages;
+        return GeneralUtility::makeInstance(TranslationConfigurationProvider::class)->getSystemLanguages($pageId);
     }
 
     /**