[WPE] Flaky crashes in ScrollingTreeFrameScrollingNodeNicosia::reposi…

…tionScrollingLayers

https://bugs.webkit.org/show_bug.cgi?id=213228

Reviewed by Adrian Perez de Castro.

When the `FrameView` delegates scrolling to a native scroll view,
we do not create a dedicated graphics layer for scrolled contents.

In this case, `static_cast<Nicosia::PlatformLayer*>(scrolledContentsLayer())`
evaluates to `nullptr` and we hit the assertion.

* LayoutTests/platform/glib/TestExpectations:
* LayoutTests/platform/wpe/TestExpectations:
* Source/WebCore/page/scrolling/nicosia/ScrollingTreeFrameScrollingNodeNicosia.cpp:
(WebCore::ScrollingTreeFrameScrollingNodeNicosia::repositionScrollingLayers):

Canonical link: https://commits.webkit.org/276274@main

LayoutTests/platform/glib/TestExpectations

@@ -3859,7 +3859,6 @@ webkit.org/b/169918 compositing/visibility/visibility-image-layers-dynamic.html
 webkit.org/b/186667 compositing/repaint/iframes/composited-iframe-with-fixed-background-doc-repaint.html [ Failure Pass ]
 # Probably categorized under the wrong bug.
 webkit.org/b/212202 compositing/fixed-with-main-thread-scrolling.html [ Timeout ]
-webkit.org/b/213228 fast/viewport/scroll-delegates-switch-on-page-with-no-composition-mode-asserts.html [ Pass Crash ]
 compositing/canvas/hidpi-canvas-backing-store-invalidation-2.html [ Failure ]
 compositing/canvas/hidpi-canvas-backing-store-invalidation.html [ Failure ]
 compositing/canvas/hidpi-canvas-backing-store.html [ Failure ]

LayoutTests/platform/wpe/TestExpectations

@@ -233,9 +233,6 @@ http/wpt/mediastream/mediastreamtrackprocessor-videoframe-timestamp.html [ Pass
 webkit.org/b/226521 [ Release ] imported/w3c/web-platform-tests/html/semantics/embedded-content/the-img-element/source-media-outside-doc.html [ Pass Failure ]
 webkit.org/b/226521 [ Debug ] imported/w3c/web-platform-tests/html/semantics/embedded-content/the-img-element/source-media-outside-doc.html [ Pass ]
 
-# Nicosia
-webkit.org/b/213228 fast/viewport/viewport-1.html [ Crash Timeout Pass ]
-
 # We don't yet support EXIF-based resolution
 webkit.org/b/217821 imported/w3c/web-platform-tests/density-size-correction/ [ Skip ]
 

Source/WebCore/page/scrolling/nicosia/ScrollingTreeFrameScrollingNodeNicosia.cpp

@@ -117,7 +117,9 @@ void ScrollingTreeFrameScrollingNodeNicosia::currentScrollPositionChanged(Scroll
 void ScrollingTreeFrameScrollingNodeNicosia::repositionScrollingLayers()
 {
     auto* scrollLayer = static_cast<Nicosia::PlatformLayer*>(scrolledContentsLayer());
-    ASSERT(scrollLayer);
+    if (!scrollLayer)
+        return;
+
     auto& compositionLayer = downcast<Nicosia::CompositionLayer>(*scrollLayer);
 
     auto scrollPosition = currentScrollPosition();