This is the second reland. Patchset 1 contains the reverted cl. Patchset 2 revert the change to initialize the encoder with resolution 1*1pixels if an internal source is used. This is to to fix the problem reported in https://codereview.webrtc.org/2457203002/ https://build.chromium.org/p/chromium.webrtc.fyi/builders/Mac%20Tester/builds/35251 remoting. Fix has been verified to work in Chrome. This reverts commit 05a55b500d83e4212d4e54f0fecf13097e782ffa. BUG=webrtc:6371 b/32285861 TBR=pbos@webrtc.org, skvlad@webrtc.org, stefan@webrtc.org Review URL: https://codereview.webrtc.org/2458363002 . Cr-Commit-Position: refs/heads/master@{#14833}