Fix markAncestorsWithChildNeedsStyleInvalidation to actually mark only ancestors.

Make corresponding fix to StyleInvalidator to not break invalidations in
which the document element itself needed invalidation.

Review URL: https://codereview.chromium.org/201443011

git-svn-id: svn://svn.chromium.org/blink/trunk@169788 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/css/invalidation/StyleInvalidator.cpp

@@ -18,10 +18,8 @@ namespace WebCore {
 
 void StyleInvalidator::invalidate()
 {
-    if (Element* documentElement = m_document.documentElement()) {
-        if (documentElement->childNeedsStyleInvalidation())
-            invalidate(*documentElement);
-    }
+    if (Element* documentElement = m_document.documentElement())
+        invalidate(*documentElement);
     m_document.clearChildNeedsStyleInvalidation();
     m_document.clearNeedsStyleInvalidation();
     m_pendingInvalidationMap.clear();

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

@@ -648,8 +648,7 @@ void Node::setNeedsStyleInvalidation()
 
 void Node::markAncestorsWithChildNeedsStyleInvalidation()
 {
-    Node* node = this;
-    for (; node && !node->childNeedsStyleInvalidation(); node = node->parentOrShadowHostNode())
+    for (Node* node = parentOrShadowHostNode(); node && !node->childNeedsStyleInvalidation(); node = node->parentOrShadowHostNode())
         node->setChildNeedsStyleInvalidation();
     if (document().childNeedsStyleInvalidation())
         document().scheduleStyleRecalc();