Disable system preview in captive portal mode

https://bugs.webkit.org/show_bug.cgi?id=241739
rdar://90563679

Reviewed by Brent Fulgham.

* Source/WebKit/WebProcess/WebPage/WebPage.cpp:
(WebKit::adjustSettingsForCaptivePortal):
Disable system preview when in captive portal mode.

Canonical link: https://commits.webkit.org/251696@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@295691 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebKit/WebProcess/WebPage/WebPage.cpp

@@ -4141,6 +4141,9 @@ static void adjustSettingsForCaptivePortal(Settings& settings, const WebPreferen
 #if ENABLE(PDFJS)
     settings.setPdfJSViewerEnabled(true);
 #endif
+#if USE(SYSTEM_PREVIEW)
+    settings.setSystemPreviewEnabled(false);
+#endif
 
     settings.setAllowedMediaContainerTypes(store.getStringValueForKey(WebPreferencesKey::mediaContainerTypesAllowedInCaptivePortalModeKey()));
     settings.setAllowedMediaCodecTypes(store.getStringValueForKey(WebPreferencesKey::mediaCodecTypesAllowedInCaptivePortalModeKey()));