Rewrite Shadow DOM distribution engine to support partial synchronous distribution for v1

third_party/WebKit/Source/core/dom/shadow/ElementShadow.cpp

Index: third_party/WebKit/Source/core/dom/shadow/ElementShadow.cpp
diff --git a/third_party/WebKit/Source/core/dom/shadow/ElementShadow.cpp b/third_party/WebKit/Source/core/dom/shadow/ElementShadow.cpp
index 597c4bf6444d43d43d26eee9908485db2862cb39..1d312a87b970b9f592687f10fc5e2e1e0b0ddd1f 100644
--- a/third_party/WebKit/Source/core/dom/shadow/ElementShadow.cpp
+++ b/third_party/WebKit/Source/core/dom/shadow/ElementShadow.cpp
@@ -254,9 +254,7 @@ bool ElementShadow::hasSameStyles(const ElementShadow* other) const
 const InsertionPoint* ElementShadow::finalDestinationInsertionPointFor(const Node* key) const
 {
     DCHECK(key);
-#if DCHECK_IS_ON()
     DCHECK(!key->needsDistributionRecalc());
-#endif
     NodeToDestinationInsertionPoints::const_iterator it = m_nodeToInsertionPoints.find(key);
     return it == m_nodeToInsertionPoints.end() ? nullptr : it->value->last();
 }
@@ -264,9 +262,7 @@ const InsertionPoint* ElementShadow::finalDestinationInsertionPointFor(const Nod
 const DestinationInsertionPoints* ElementShadow::destinationInsertionPointsFor(const Node* key) const
 {
     DCHECK(key);
-#if DCHECK_IS_ON()
     DCHECK(!key->needsDistributionRecalc());
-#endif
     NodeToDestinationInsertionPoints::const_iterator it = m_nodeToInsertionPoints.find(key);
     return it == m_nodeToInsertionPoints.end() ? nullptr : it->value;
 }