List marker pseudo elements.

Source/core/dom/Element.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1507 matching lines @@
     ContainerNode::attach(context);
 
     createPseudoElementIfNeeded(AFTER);
     createPseudoElementIfNeeded(BACKDROP);
 
     // We create the first-letter element after the :before, :after and
     // children are attached because the first letter text could come
     // from any of them.
     createPseudoElementIfNeeded(FIRST_LETTER);
 
+    // The marker has to come after the other content, including the BEFORE pseudo
+    // element so make sure we create it last.
+    if (RuntimeEnabledFeatures::listMarkerPseudoElementEnabled())
+        createPseudoElementIfNeeded(MARKER);
+
     if (hasRareData() && !layoutObject()) {
         if (ElementAnimations* elementAnimations = elementRareData()->elementAnimations()) {
             elementAnimations->cssAnimations().cancel();
             elementAnimations->setAnimationStyleChange(false);
         }
     }
 }
 
 void Element::detach(const AttachContext& context)
 {
@@ skipping 146 matching lines @@
         if (change > UpdatePseudoElements || childNeedsStyleRecalc()) {
             for (ShadowRoot* root = youngestShadowRoot(); root; root = root->olderShadowRoot()) {
                 if (root->shouldCallRecalcStyle(change))
                     root->recalcStyle(change);
             }
             recalcChildStyle(change);
         }
 
         updatePseudoElement(AFTER, change);
         updatePseudoElement(BACKDROP, change);
+        if (RuntimeEnabledFeatures::listMarkerPseudoElementEnabled())
+            updatePseudoElement(MARKER, change);
 
         // If our children have changed then we need to force the first-letter
         // checks as we don't know if they effected the first letter or not.
         // This can be seen when a child transitions from floating to
         // non-floating we have to take it into account for the first letter.
         updatePseudoElement(FIRST_LETTER, childNeedsStyleRecalc() ? Force : change);
 
         clearChildNeedsStyleRecalc();
     }
 
@@ skipping 1046 matching lines @@
             layoutObject()->mutableStyle()->removeCachedPseudoStyle(pseudoId);
 
         // PseudoElement styles hang off their parent element's style so if we needed
         // a style recalc we should Force one on the pseudo.
         // FIXME: We should figure out the right text sibling to pass.
         element->recalcStyle(change == UpdatePseudoElements ? Force : change);
 
         // Wait until our parent is not displayed or pseudoElementRendererIsNeeded
         // is false, otherwise we could continuously create and destroy PseudoElements
         // when LayoutObject::isChildAllowed on our parent returns false for the
-        // PseudoElement's renderer for each style recalc.
-        if (!layoutObject() || !pseudoElementRendererIsNeeded(layoutObject()->getCachedPseudoStyle(pseudoId)))
+        // PseudoElement's layoutObject for each style recalc.
+        if (!layoutObject()
+            || (!pseudoElementRendererIsNeeded(layoutObject()->getCachedPseudoStyle(pseudoId))
+                && (pseudoId == MARKER && layoutObject()->style()->display() != LIST_ITEM))) {

[esprehn, 2015/04/22 07:45:45]

What's up with this check for != LIST_ITEM all over?

[dsinclair, 2015/04/22 20:00:38]

If you have something like: <div style="display: list-item"> it will have a
MARKER, but, we then change to display:block we're going to have a MARKER but no
longer be a list item. In that case, we have to destroy the MARKER as it's no
longer valid.

             elementRareData()->setPseudoElement(pseudoId, nullptr);
+        }
     } else if (pseudoId == FIRST_LETTER && element && change >= UpdatePseudoElements && !FirstLetterPseudoElement::firstLetterTextRenderer(*element)) {
         // This can happen if we change to a float, for example. We need to cleanup the
         // first-letter pseudoElement and then fix the text of the original remaining
         // text renderer.
         // This can be seen in Test 7 of fast/css/first-letter-removed-added.html
         elementRareData()->setPseudoElement(pseudoId, nullptr);
     } else if (change >= UpdatePseudoElements) {
         createPseudoElementIfNeeded(pseudoId);
     }
 }
@@ skipping 13 matching lines @@
             element->reattach();
         else
             elementRareData()->setPseudoElement(FIRST_LETTER, nullptr);
         return true;
     }
     return false;
 }
 
 void Element::createPseudoElementIfNeeded(PseudoId pseudoId)
 {
-    if (isPseudoElement())
+    if (isPseudoElement() && (pseudoId != MARKER || isMarkerPseudoElement()))

[esprehn, 2015/04/22 07:45:45]

Marker shouldn't need a special case here. PseudoElements can never have nested
pseudo elements. This branch doesn't need to change.

[dsinclair, 2015/04/22 20:00:38]

With marker they can. If we have something like:

    #a:after {
        display: list-item;
        content: "ONE";
    }

Then the ::after pseudo element will have a ::marker pseudo element under it.
Added a comment.

         return;
 
     // Document::ensureStyleResolver is not inlined and shows up on profiles, avoid it here.
-    RefPtrWillBeRawPtr<PseudoElement> element = document().styleEngine().ensureResolver().createPseudoElementIfNeeded(*this, pseudoId);
+    RefPtrWillBeRawPtr<PseudoElement> element =  document().styleEngine().ensureResolver().createPseudoElementIfNeeded(*this, pseudoId);
     if (!element)
         return;
-
     if (pseudoId == BACKDROP)
         document().addToTopLayer(element.get(), this);
+
     element->insertedInto(this);
     element->attach();
 
     InspectorInstrumentation::pseudoElementCreated(element.get());
 
     ensureElementRareData().setPseudoElement(pseudoId, element.release());
 }
 
 PseudoElement* Element::pseudoElement(PseudoId pseudoId) const
 {
@@ skipping 696 matching lines @@
 {
 #if ENABLE(OILPAN)
     if (hasRareData())
         visitor->trace(elementRareData());
     visitor->trace(m_elementData);
 #endif
     ContainerNode::trace(visitor);
 }
 
 } // namespace blink