Delete deprecated and transitional stuff related to video frame refactoring.

BUG=webrtc:5880

Review-Url: https://codereview.webrtc.org/2622263002
Cr-Original-Commit-Position: refs/heads/master@{#17928}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 713a3bbcc74a4c1a1f54d6dbd0bdaa715f5c1ae1
26 files changed