WIP (Introduce WTF::NonNullPtr<T>.)

Source/core/dom/shadow/InsertionPoint.cpp

Index: Source/core/dom/shadow/InsertionPoint.cpp
diff --git a/Source/core/dom/shadow/InsertionPoint.cpp b/Source/core/dom/shadow/InsertionPoint.cpp
index 7d05daaf2b336d464a6778eca6fd33cef156edba..537a2e8ae08a394d6785a79744e934f93b698f36 100644
--- a/Source/core/dom/shadow/InsertionPoint.cpp
+++ b/Source/core/dom/shadow/InsertionPoint.cpp
@@ -175,7 +175,7 @@ Node::InsertionNotificationRequest InsertionPoint::insertedInto(ContainerNode* i
     if (ShadowRoot* root = containingShadowRoot()) {
         if (ElementShadow* rootOwner = root->owner()) {
             rootOwner->setNeedsDistributionRecalc();
-            if (isActive() && !m_registeredWithShadowRoot && insertionPoint->treeScope().rootNode() == root) {
+            if (isActive() && !m_registeredWithShadowRoot && insertionPoint->treeScope()->rootNode() == root) {
                 m_registeredWithShadowRoot = true;
                 root->addInsertionPoint(this);
                 rootOwner->didAffectApplyAuthorStyles();
@@ -205,7 +205,7 @@ void InsertionPoint::removedFrom(ContainerNode* insertionPoint)
     // Since this insertion point is no longer visible from the shadow subtree, it need to clean itself up.
     clearDistribution();
 
-    if (m_registeredWithShadowRoot && insertionPoint->treeScope().rootNode() == root) {
+    if (m_registeredWithShadowRoot && insertionPoint->treeScope()->rootNode() == root) {
         ASSERT(root);
         m_registeredWithShadowRoot = false;
         root->removeInsertionPoint(this);