Update an Element's ancestor chain at the end of its activation

Source/core/dom/Document.cpp

Index: Source/core/dom/Document.cpp
diff --git a/Source/core/dom/Document.cpp b/Source/core/dom/Document.cpp
index d3ff7e416ef064d37ab0cf9a617667826fd9bde1..ed0391764a5fd5cd65787f40c78e38cc331beebf 100644
--- a/Source/core/dom/Document.cpp
+++ b/Source/core/dom/Document.cpp
@@ -5455,6 +5455,14 @@ void Document::updateHoverActiveState(const HitTestRequest& request, Element* in
                 m_userActionElements.setInActiveChain(curr->node(), false);
             }
         }
+        // The oldActiveElement renderer is null, dropped on :active by setting display: none,
+        // for instance. We still need to clear the ActiveChain as the mouse is released.
+        if (!oldActiveElement->renderer()) {
+            for (Node* node = oldActiveElement; node; node = node->parentNode()) {

[esprehn, 2014/06/17 08:37:20]

This is not correct for Shadow DOM. You need to use
NodeRenderingTraversal::parent(). You should also just be able to modify the
loop above to use that. That also doesn't seem quite right though since you
could change the distribution and break the parentNode() chain. Perhaps
::detach() should clear the bits? What does Firefox do here?

[spartha, 2014/06/17 15:07:00]

I tried this content http://jsbin.com/fasoyuqi on firefox nightly and Chrome
with my patch. As you have correctly pointed out, using parentNode() fails to
restore the style for the shadow DOM elements. The same content on Firefox
nightly is inconclusive as the shadow DOM implementation is still not very
mature. As far as the behaviour without shadow DOM, Firefox restores the non
active state for all the active chain elements at the end of active state.

Thanks for the insight...

[spartha, 2014/06/18 12:40:09]

I have uploaded a patch using NodeRenderingTraversal, PTAL. I quite did not get
the scenario where chaning the distribution could be a problem. 

+                node->setActive(false);
+                m_userActionElements.setInActiveChain(node, false);
+            }
+        }
         setActiveHoverElement(nullptr);
     } else {
         Element* newActiveElement = innerElementInDocument;