[master] Update dependencies from 4 repositories (dotnet/corefx#39384)

[master] Update dependencies from 4 repositories (dotnet/corefx#39384)

* Update dependencies from https://github.com/dotnet/core-setup build 20190711.01

- Microsoft.NETCore.App - 3.0.0-preview8-27911-01
- Microsoft.NETCore.DotNetHostPolicy - 3.0.0-preview8-27911-01
- Microsoft.NETCore.DotNetHost - 3.0.0-preview8-27911-01

* Update dependencies from https://github.com/dotnet/corefx build 20190710.10

- runtime.native.System.IO.Ports - 4.6.0-preview8.19360.10
- Microsoft.NETCore.Platforms - 3.0.0-preview8.19360.10

* Update dependencies from https://dev.azure.com/dnceng/internal/_git/dotnet-optimization build 20190711.1

- optimization.windows_nt-x64.IBC.CoreFx - 99.99.99-master-20190711.1

* Update dependencies from https://github.com/dotnet/standard build 20190711.1

- NETStandard.Library - 2.1.0-prerelease.19361.1

* Update dependencies from https://github.com/dotnet/standard build 20190711.2

- NETStandard.Library - 2.1.0-prerelease.19361.2

* Update APICompat baseline

* Update dependencies from https://github.com/dotnet/standard build 20190711.3

- NETStandard.Library - 2.1.0-prerelease.19361.3

Commit migrated from https://github.com/dotnet/corefx/commit/ac154845e79c6154c2b502aa3cdd4410e1b5f2b0