* Add a screen_api_id parameter to the desktopCapturer API.
When using the DirectX capturer on Windows, there was previously no way
to associate desktopCapturer/getUserMedia and electron.screen API
screens. This new parameter provides the association.
* Fix non-Windows build.
* Fix Mac.
* Fix Mac harder.
* JS lint
* clang-format C++ code.
* IWYU
* display_id, Linux comment, better test
* lint
* Fix tests on Linux.
* Add display_id documentation.
