- CefURLRequest::Create is no longer supported in the renderer process
(see https://crbug.com/891872). Use CefFrame::CreateURLRequest instead.
- Mac platform definitions have been changed from `MACOSX` to `MAC`
(see https://crbug.com/1105907) and related CMake macro names have
been updated. The old `OS_MACOSX` define is still set in code and CMake
for backwards compatibility.
- Linux ARM build is currently broken (see https://crbug.com/1123214).
- Windows: 10.0.19041 SDK is now required.
- macOS: 10.15.1 SDK (at least Xcode 11.2) is now required.
- Remove CefMediaSource::IsValid and CefMediaSink::IsValid which would
always return true.
