Add support for SVG Clip paths in HTML

Source/core/rendering/RenderLayer.cpp

Index: Source/core/rendering/RenderLayer.cpp
diff --git a/Source/core/rendering/RenderLayer.cpp b/Source/core/rendering/RenderLayer.cpp
index ea83bc9e465458e5b59d3e73b430a8b72a3eb3e3..17401aeda2daafa8fe6154e781412250bc707934 100644
--- a/Source/core/rendering/RenderLayer.cpp
+++ b/Source/core/rendering/RenderLayer.cpp
@@ -118,6 +118,7 @@ RenderLayer::RenderLayer(RenderLayerModelObject* renderer, LayerType type)
     , m_has3DTransformedDescendant(false)
     , m_containsDirtyOverlayScrollbars(false)
     , m_hasFilterInfo(false)
+    , m_hasClipPathInfo(false)
     , m_needsAncestorDependentCompositingInputsUpdate(true)
     , m_needsDescendantDependentCompositingInputsUpdate(true)
     , m_childNeedsCompositingInputsUpdate(true)
@@ -162,6 +163,7 @@ RenderLayer::~RenderLayer()
     }
 
     removeFilterInfoIfNeeded();
+    removeClipPathInfoIfNeeded();
 
     if (groupedMapping()) {
         DisableCompositingQueryAsserts disabler;
@@ -3549,6 +3551,27 @@ void RenderLayer::updateFilters(const RenderStyle* oldStyle, const RenderStyle*
     updateOrRemoveFilterEffectRenderer();
 }
 
+void RenderLayer::updateClipPath(const RenderStyle* oldStyle, const RenderStyle* newStyle)
+{
+    if (!newStyle->clipPath() && (!oldStyle || !oldStyle->clipPath()))
+        return;
+
+    updateOrRemoveClipPathClients();
+}
+
+void RenderLayer::updateOrRemoveClipPathClients()
+{
+    if (!hasClipPath()) {
+        removeClipPathInfoIfNeeded();
+        return;
+    }
+
+    if (renderer()->style()->clipPath()->type() == ClipPathOperation::REFERENCE)
+        ensureClipPathInfo()->updateReferenceClipPathClients(renderer()->style()->clipPath());
+    else if (hasClipPathInfo())
+        clipPathInfo()->removeReferenceClipPathClients();
+}
+
 bool RenderLayer::attemptDirectCompositingUpdate(StyleDifference diff, const RenderStyle* oldStyle)
 {
     CompositingReasons oldPotentialCompositingReasonsFromStyle = m_potentialCompositingReasonsFromStyle;
@@ -3634,6 +3657,7 @@ void RenderLayer::styleChanged(StyleDifference diff, const RenderStyle* oldStyle
 
     updateTransform(oldStyle, renderer()->style());
     updateFilters(oldStyle, renderer()->style());
+    updateClipPath(oldStyle, renderer()->style());
 
     setNeedsCompositingInputsUpdate();
 }