Delete method webrtc::VideoFrame::allocated_size and enum PlaneType.

BUG=webrtc:5682

Review-Url: https://codereview.webrtc.org/2380623002
Cr-Original-Commit-Position: refs/heads/master@{#14416}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: e5684c5387bbc2cbbca80eefc3e3f6474c180647
8 files changed