Revert of "Implement the inert attribute"

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 21488ccec25880912253e826ccd5dea17217403c..dcdb71f0bed37739deb2b2c0e62b29da6c3c872e 100644
--- a/third_party/WebKit/Source/core/dom/Node.cpp
+++ b/third_party/WebKit/Source/core/dom/Node.cpp
@@ -755,9 +755,8 @@ void Node::MarkAncestorsWithChildNeedsStyleInvalidation() {
 void Node::MarkAncestorsWithChildNeedsDistributionRecalc() {
   ScriptForbiddenScope forbid_script_during_raw_iteration;
   for (Node* node = this; node && !node->ChildNeedsDistributionRecalc();
-       node = node->ParentOrShadowHostNode()) {
+       node = node->ParentOrShadowHostNode())
     node->SetChildNeedsDistributionRecalc();
-  }
   GetDocument().ScheduleLayoutTreeUpdateIfNeeded();
 }
 
@@ -849,27 +848,11 @@ bool Node::ShouldHaveFocusAppearance() const {
 }
 
 bool Node::IsInert() const {
-  if (!isConnected() || !CanParticipateInFlatTree())
-    return true;
-
-  DCHECK(!ChildNeedsDistributionRecalc());
-
   const HTMLDialogElement* dialog = GetDocument().ActiveModalDialog();
   if (dialog && this != GetDocument() &&
-      !FlatTreeTraversal::ContainsIncludingPseudoElement(*dialog, *this)) {
+      (!CanParticipateInFlatTree() ||
+       !FlatTreeTraversal::ContainsIncludingPseudoElement(*dialog, *this)))
     return true;
-  }
-
-  if (RuntimeEnabledFeatures::inertAttributeEnabled()) {
-    const Element* element = this->IsElementNode()
-                                 ? ToElement(this)
-                                 : FlatTreeTraversal::ParentElement(*this);
-    while (element) {
-      if (element->hasAttribute(HTMLNames::inertAttr))
-        return true;
-      element = FlatTreeTraversal::ParentElement(*element);
-    }
-  }
   return GetDocument().LocalOwner() && GetDocument().LocalOwner()->IsInert();
 }