Revert of Support slot element's fallback content feature

third_party/WebKit/Source/core/html/HTMLSlotElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLSlotElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLSlotElement.cpp b/third_party/WebKit/Source/core/html/HTMLSlotElement.cpp
index a3f1e37a55b40d6af3eecd960ff06567795d1f07..cf907c221c755daa2c33147e415d07648ad7d523 100644
--- a/third_party/WebKit/Source/core/html/HTMLSlotElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLSlotElement.cpp
@@ -31,8 +31,6 @@
 #include "core/html/HTMLSlotElement.h"
 
 #include "core/HTMLNames.h"
-#include "core/dom/NodeTraversal.h"
-#include "core/dom/shadow/InsertionPoint.h"
 
 namespace blink {
 
@@ -100,21 +98,6 @@
     HTMLElement::detach(context);
 }
 
-void HTMLSlotElement::updateDistributedNodesWithFallback()
-{
-    if (!m_distributedNodes.isEmpty())
-        return;
-    for (auto& child : NodeTraversal::childrenOf(*this)) {
-        // Insertion points are not supported as slots fallback
-        if (isActiveInsertionPoint(child))
-            continue;
-        if (isHTMLSlotElement(child))
-            appendDistributedNodes(toHTMLSlotElement(child).getDistributedNodes());
-        else
-            appendDistributedNode(child);
-    }
-}
-
 DEFINE_TRACE(HTMLSlotElement)
 {
     visitor->trace(m_assignedNodes);