Support the essential part of Shadow DOM v1

third_party/WebKit/Source/core/dom/Node.cpp

Index: third_party/WebKit/Source/core/dom/Node.cpp
diff --git a/third_party/WebKit/Source/core/dom/Node.cpp b/third_party/WebKit/Source/core/dom/Node.cpp
index c76642f61dd995eb592dc5bf45c00116d42a44ad..51c634b97c06438ad5a9496c91e535f0089371b2 100644
--- a/third_party/WebKit/Source/core/dom/Node.cpp
+++ b/third_party/WebKit/Source/core/dom/Node.cpp
@@ -79,6 +79,7 @@
 #include "core/frame/LocalFrame.h"
 #include "core/html/HTMLDialogElement.h"
 #include "core/html/HTMLFrameOwnerElement.h"
+#include "core/html/HTMLSlotElement.h"
 #include "core/input/EventHandler.h"
 #include "core/layout/LayoutBox.h"
 #include "core/page/ContextMenuController.h"
@@ -960,7 +961,12 @@ bool Node::canStartSelection() const
 
 bool Node::canParticipateInComposedTree() const
 {
-    return !isShadowRoot() && !isActiveInsertionPoint(*this);
+    return !isShadowRoot() && !isSlotOrActiveInsertionPoint();
+}
+
+bool Node::isSlotOrActiveInsertionPoint() const
+{
+    return isHTMLSlotElement(*this) || isActiveInsertionPoint(*this);
 }
 
 Element* Node::shadowHost() const
@@ -2203,6 +2209,19 @@ PassRefPtrWillBeRawPtr<StaticNodeList> Node::getDestinationInsertionPoints()
     return StaticNodeList::adopt(filteredInsertionPoints);
 }
 
+HTMLSlotElement* Node::assignedSlot() const
+{
+    ASSERT(!needsDistributionRecalc());
+    Element* parent = parentElement();
+    if (!parent)
+        return nullptr;
+    if (ElementShadow* shadow = parent->shadow()) {
+        if (shadow->isV1())
+            return shadow->assignedSlotFor(*this);
+    }
+    return nullptr;
+}
+
 void Node::setFocus(bool flag)
 {
     document().userActionElements().setFocused(this, flag);