Revert of Move CoreVideoFrameBuffer from webrtc/common_video/ to webrtc/sdk/objc/ (patchset #2 id:60001 of https://codereview.webrtc.org/2851563003/ )

Reason for revert:
Breaks downstream targets.

Original issue's description:
> Move CoreVideoFrameBuffer from webrtc/common_video/ to webrtc/sdk/objc/
>
> CoreVideoFrameBuffer is Mac/iPhone specific and should be moved into
> the webrtc/sdk/objc/ folder.
>
> BUG=None
>
> Review-Url: https://codereview.webrtc.org/2851563003
> Cr-Commit-Position: refs/heads/master@{#17998}
> Committed: https://chromium.googlesource.com/external/webrtc/+/d41631aa274e926c4fba1600cbcfbc18020eb35a

TBR=kthelgason@webrtc.org,magjed@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=None

Review-Url: https://codereview.webrtc.org/2862663003
Cr-Commit-Position: refs/heads/master@{#18004}
12 files changed
tree: eeb3b7b5c8b2a6c44debde46c35c2a60e129c775
  1. build_overrides/
  2. data/
  3. infra/
  4. resources/
  5. tools-webrtc/
  6. webrtc/
  7. .clang-format
  8. .git-blame-ignore-revs
  9. .gitignore
  10. .gn
  11. AUTHORS
  12. BUILD.gn
  13. check_root_dir.py
  14. cleanup_links.py
  15. codereview.settings
  16. DEPS
  17. LICENSE
  18. license_template.txt
  19. LICENSE_THIRD_PARTY
  20. OWNERS
  21. PATENTS
  22. PRESUBMIT.py
  23. pylintrc
  24. README.md
  25. WATCHLISTS
README.md

WebRTC is a free, open software project that provides browsers and mobile applications with Real-Time Communications (RTC) capabilities via simple APIs. The WebRTC components have been optimized to best serve this purpose.

Our mission: To enable rich, high-quality RTC applications to be developed for the browser, mobile platforms, and IoT devices, and allow them all to communicate via a common set of protocols.

The WebRTC initiative is a project supported by Google, Mozilla and Opera, amongst others.

Development

See http://www.webrtc.org/native-code/development for instructions on how to get started developing with the native code.

More info