Cherry-pick da1f448. rdar://121400620

    REGRESSION: Google search results are cropped when viewing in the smallest window size
    https://bugs.webkit.org/show_bug.cgi?id=268845
    rdar://121400620

    Reviewed by Aditya Keerthi.

    * Source/WebKit/UIProcess/API/ios/WKWebViewIOS.mm:
    (-[WKWebView _isWindowResizingEnabled]):
    _enhancedWindowingEnabled was recently flipped on (which is correct), but caused
    some unexpected viewport regressions on visionOS. To maintain the status quo,
    override it to NO for the time being.

    Canonical link: https://commits.webkit.org/274173@main

Identifier: 272448.531@safari-7618.1.15.14-branch

Source/WebKit/UIProcess/API/ios/WKWebViewIOS.mm

@@ -1747,7 +1747,12 @@ - (void)didMoveToWindow
 
 - (BOOL)_isWindowResizingEnabled
 {
+#if PLATFORM(VISION)
+    // This is technically incorrect, but matches longstanding behavior, and avoids layout regressions on visionOS.
+    return NO;
+#else
     return self.window.windowScene._enhancedWindowingEnabled;
+#endif
 }
 
 #endif // HAVE(UIKIT_RESIZABLE_WINDOWS)