Avoid false-positives of under-invalidation checking

Source/core/paint/HTMLCanvasPainter.cpp

Index: Source/core/paint/HTMLCanvasPainter.cpp
diff --git a/Source/core/paint/HTMLCanvasPainter.cpp b/Source/core/paint/HTMLCanvasPainter.cpp
index 22aaa1550189d105c16965350b57935a3ef85dc0..c0c476acac87b7dffc1aaf53436d78fb9a9f19d2 100644
--- a/Source/core/paint/HTMLCanvasPainter.cpp
+++ b/Source/core/paint/HTMLCanvasPainter.cpp
@@ -27,6 +27,11 @@ void HTMLCanvasPainter::paintReplaced(const PaintInfo& paintInfo, const LayoutPo
     if (drawingRecorder.canUseCachedDrawing())
         return;
 
+#if ENABLE(ASSERT)
+    // The drawing may be in display list mode or image mode, producing different pictures for the same result.
+    drawingRecorder.setUnderInvalidationCheckingMode(DrawingDisplayItem::CheckBitmap);
+#endif
+
     bool clip = !contentRect.contains(paintRect);
     if (clip) {
         context->save();