Implement will-change-based GPU rasterization hint

Source/core/rendering/compositing/CompositingReasonFinder.cpp

Index: Source/core/rendering/compositing/CompositingReasonFinder.cpp
diff --git a/Source/core/rendering/compositing/CompositingReasonFinder.cpp b/Source/core/rendering/compositing/CompositingReasonFinder.cpp
index 7755f81b988691a05226110fc5a4350d0a0cd76d..a65ae9056e53ac1b3842a3553ee70e436c62d7c9 100644
--- a/Source/core/rendering/compositing/CompositingReasonFinder.cpp
+++ b/Source/core/rendering/compositing/CompositingReasonFinder.cpp
@@ -263,7 +263,15 @@ bool CompositingReasonFinder::requiresCompositingForOutOfFlowClipping(const Rend
 
 bool CompositingReasonFinder::requiresCompositingForWillChange(const RenderObject* renderer) const
 {
-    return renderer->style()->hasWillChangeCompositingHint();
+    if (renderer->style()->hasWillChangeCompositingHint())
+        return true;
+
+    if (Settings* settings = m_renderView.document().settings()) {
+        if (!settings->acceleratedCompositingForGpuRasterizationHintEnabled())
+            return false;
+    }
+
+    return renderer->style()->hasWillChangeGpuRasterizationHint();
 }
 
 bool CompositingReasonFinder::isViewportConstrainedFixedOrStickyLayer(const RenderLayer* layer)