Support slotchange events

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 832a32753ea3be8d7e1d126a70b68b588392669c..0faaa79eb4ad5664792a2ebc49d8749d3b10408b 100644
--- a/third_party/WebKit/Source/core/dom/Node.cpp
+++ b/third_party/WebKit/Source/core/dom/Node.cpp
@@ -44,6 +44,7 @@
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/LayoutTreeBuilderTraversal.h"
+#include "core/dom/Microtask.h"
 #include "core/dom/NodeRareData.h"
 #include "core/dom/NodeTraversal.h"
 #include "core/dom/ProcessingInstruction.h"
@@ -690,6 +691,11 @@ void Node::markAncestorsWithChildNeedsStyleInvalidation()
 void Node::markAncestorsWithChildNeedsDistributionRecalc()
 {
     ScriptForbiddenScope forbidScriptDuringRawIteration;
+    if (inDocument() && !document().childNeedsDistributionRecalc()) {
+        // TODO(hayato): Support a non-document composed tree.
+        // TODO(hayato): Enqueue a task only if a 'slotchange' event listner is registered in the document composed tree.
+        Microtask::enqueueMicrotask(WTF::bind(&Document::updateDistribution, &document()));

[yhirano, 2016/02/17 05:23:12]

WTF::bind stores an off-heap pointer as is. Shouldn't we store
PassRefPtrWillBeRawPtr instead?

[hayato, 2016/02/17 06:07:33]

Good point. Done.
Could you check again whether I understand the point correctly?

+    }
     for (Node* node = this; node && !node->childNeedsDistributionRecalc(); node = node->parentOrShadowHostNode())
         node->setChildNeedsDistributionRecalc();
     document().scheduleLayoutTreeUpdateIfNeeded();