The Canvas tab is now able to entirely replace the old Resource/Recording tab UI. We can remove it and the flag that controls the Canvas tab.
Created attachment 324650 [details] Patch
<rdar://problem/35157502>
Comment on attachment 324650 [details] Patch r=me
Comment on attachment 324650 [details] Patch Will land manually.
Committed r223920: <https://trac.webkit.org/changeset/223920>