Revert the feature of the <shadow> element as 'a function call' to the previous behavior.

Source/core/dom/shadow/ElementShadow.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 258 matching lines @@
     DistributionPool pool(*host());
 
     for (ShadowRoot* root = youngestShadowRoot(); root; root = root->olderShadowRoot()) {
         HTMLShadowElement* shadowInsertionPoint = 0;
         const Vector<RefPtr<InsertionPoint> >& insertionPoints = root->descendantInsertionPoints();
         for (size_t i = 0; i < insertionPoints.size(); ++i) {
             InsertionPoint* point = insertionPoints[i].get();
             if (!point->isActive())
                 continue;
             if (point->hasTagName(HTMLNames::shadowTag)) {
-                if (!shadowInsertionPoint)
-                    shadowInsertionPoint = toHTMLShadowElement(point);
+                ASSERT(!shadowInsertionPoint);
+                shadowInsertionPoint = toHTMLShadowElement(point);
+                shadowInsertionPoints.append(shadowInsertionPoint);
             } else {
                 pool.distributeTo(point, this);
                 if (ElementShadow* shadow = shadowWhereNodeCanBeDistributed(*point))
                     shadow->setNeedsDistributionRecalc();
             }
         }
-        if (shadowInsertionPoint) {
-            shadowInsertionPoints.append(shadowInsertionPoint);
-            if (shadowInsertionPoint->hasChildNodes())
-                pool.populateChildren(*shadowInsertionPoint);
-        } else {
-            pool.clear();
-        }
     }
 
     for (size_t i = shadowInsertionPoints.size(); i > 0; --i) {
         HTMLShadowElement* shadowInsertionPoint = shadowInsertionPoints[i - 1];
         ShadowRoot* root = shadowInsertionPoint->containingShadowRoot();
         ASSERT(root);
         if (root->isOldest()) {
             pool.distributeTo(shadowInsertionPoint, this);
         } else if (root->olderShadowRoot()->type() == root->type()) {
             // Only allow reprojecting older shadow roots between the same type to
@@ skipping 61 matching lines @@
 
 void ElementShadow::clearDistribution()
 {
     m_nodeToInsertionPoints.clear();
 
     for (ShadowRoot* root = youngestShadowRoot(); root; root = root->olderShadowRoot())
         root->setShadowInsertionPointOfYoungerShadowRoot(0);
 }
 
 } // namespace