Add DesktopCapturer GetSourceList SelectSource FocusOnSelectedSource functions

I have chosen part of 2435603010 changes to compose this change.
According to the discussion we have made in previous change, this CL contains,
1. Source structure to represent a source of a DesktopCapturer.
2. GetSourceList / SelectSource / FocusOnSelectedSource functions in
DesktopCapturer.
3. ScreenCapturer and WindowCapturer forward corresponding functions to the new
DesktopCapturer APIs.

After this change, We can remove WindowCapturer & ScreenCapturer references from
Chromium, and use the new APIs.

BUG=webrtc:6513

Review-Url: https://codereview.webrtc.org/2452263003
Cr-Commit-Position: refs/heads/master@{#14830}
9 files changed
tree: e37138e00675326d2373008e8b255e8e3622b97e
  1. build_overrides/
  2. chromium/
  3. data/
  4. infra/
  5. resources/
  6. third_party/
  7. tools/
  8. webrtc/
  9. .clang-format
  10. .git-blame-ignore-revs
  11. .gitignore
  12. .gn
  13. all.gyp
  14. AUTHORS
  15. BUILD.gn
  16. check_root_dir.py
  17. codereview.settings
  18. DEPS
  19. LICENSE
  20. license_template.txt
  21. LICENSE_THIRD_PARTY
  22. OWNERS
  23. PATENTS
  24. PRESUBMIT.py
  25. pylintrc
  26. README.md
  27. setup_links.py
  28. sync_chromium.py
  29. 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. This page is maintained by the Google Chrome team.

Development

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

More info