Delete static method TaskQueue::IsCurrent. The static method takes a queue name as argument. Used only in one place, a DCHECK in IncomingVideoStream, which is converted to use the non-static version of IsCurrent. BUG=webrtc:8166 Review-Url: https://codereview.webrtc.org/3004873002 Cr-Original-Commit-Position: refs/heads/master@{#19657} Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc Cr-Mirrored-Commit: 2c7b7a633f6a6aef4467cc3b35a056a4dcc9d619