Skip child ShadowRoots when invalidation does not have boundary crossing rules

Source/core/css/invalidation/StyleInvalidator.cpp

Index: Source/core/css/invalidation/StyleInvalidator.cpp
diff --git a/Source/core/css/invalidation/StyleInvalidator.cpp b/Source/core/css/invalidation/StyleInvalidator.cpp
index 39fb027fdba4805885ac8874bede480d3cc688ce..ff09a69f16077e69ccb49f394a73d6b9898bfe6c 100644
--- a/Source/core/css/invalidation/StyleInvalidator.cpp
+++ b/Source/core/css/invalidation/StyleInvalidator.cpp
@@ -75,6 +75,8 @@ void StyleInvalidator::RecursionData::pushInvalidationSet(const DescendantInvali
         m_wholeSubtreeInvalid = true;
         return;

[chrishtr, 2014/05/29 20:54:07]

Move tree boundary crossing before this early return conditional.

[esprehn, 2014/05/29 21:07:30]

That would make us traverse too far down the tree when wholeSubtreeInvalid is
true, but I should probably fix that in a separate patch. I'll move this.

     }
+    if (invalidationSet.treeBoundaryCrossing())
+        m_treeBoundaryCrossing = true;
     m_invalidationSets.append(&invalidationSet);
     m_invalidateCustomPseudo = invalidationSet.customPseudoInvalid();
 }
@@ -115,14 +117,16 @@ bool StyleInvalidator::invalidateChildren(Element& element)
 {
     bool someChildrenNeedStyleRecalc = false;
     for (ShadowRoot* root = element.youngestShadowRoot(); root; root = root->olderShadowRoot()) {
-        for (Element* child = ElementTraversal::firstWithin(*root); child; child = ElementTraversal::nextSibling(*child)) {
+        if (!m_recursionData.treeBoundaryCrossing() && !root->childNeedsStyleInvalidation() && !root->needsStyleInvalidation())
+            continue;
+        for (Element* child = ElementTraversal::firstChild(*root); child; child = ElementTraversal::nextSibling(*child)) {
             bool childRecalced = invalidate(*child);
             someChildrenNeedStyleRecalc = someChildrenNeedStyleRecalc || childRecalced;
         }
         root->clearChildNeedsStyleInvalidation();
         root->clearNeedsStyleInvalidation();
     }
-    for (Element* child = ElementTraversal::firstWithin(element); child; child = ElementTraversal::nextSibling(*child)) {
+    for (Element* child = ElementTraversal::firstChild(element); child; child = ElementTraversal::nextSibling(*child)) {
         bool childRecalced = invalidate(*child);
         someChildrenNeedStyleRecalc = someChildrenNeedStyleRecalc || childRecalced;
     }