setTargetAttributeAnimatedValue should check for a null shadowTreeElement.
Created attachment 77392 [details] Patch
I dont' really understand shadowtree pruning. But I suspect Niko does.
I bug Niko a lot. I thought I'd give him a reprieve for the holidays since I'm just cleaning out some annoyance bugs that I'd stumbled on while fixing security issues. :)
Good catch Justin, happy x-mas! :-)
The commit-queue encountered the following flaky tests while processing attachment 77392 [details]: inspector/elements-panel-styles.html bug 50987 (author: pfeldman@chromium.org) The commit-queue is continuing to process your patch.
Comment on attachment 77392 [details] Patch Clearing flags on attachment: 77392 Committed r74629: <http://trac.webkit.org/changeset/74629>
All reviewed patches have been landed. Closing bug.