It seems weird that TreeScope has isShadowRoot(). We should do treeScope->rootNode()->isShadowRoot. Since rootNode() is inlined, the overall performance won't change.
Because of this existence, some code requires to include non-necessary ShadowRoot.h...
Created attachment 135080 [details] Patch
Comment on attachment 135080 [details] Patch Clearing flags on attachment: 135080 Committed r112978: <http://trac.webkit.org/changeset/112978>
All reviewed patches have been landed. Closing bug.