TreeView.HasFocus is false when TreeView has the focus

[netonjm]

As well Lost/Got focus event is not propagating as expected when it gains/lost the focus.

=== MonoDevelop ===

Version 7.8 Preview (7.8)
Installation UUID: 4027e73c-9660-4f9f-981e-96efbceb3f7d
Runtime:
Mono 5.12.0.305 (2018-02/e0e035e3b14 Wed Aug 22 09:24:11 EDT 2018) (64-bit)
GTK+ 2.24.23 (Raleigh theme)
Xamarin.Mac 4.99.3.658 ( / 1eefd4e3)

Package version: 512000305

=== NuGet ===

Version: 4.3.1.4445

=== .NET Core ===

Runtime: /usr/local/share/dotnet/dotnet
Runtime Versions:
2.1.2
2.1.1
2.0.5
2.0.3
2.0.0
1.1.2
1.1.1
1.0.5
1.0.4
1.0.3
SDK: /usr/local/share/dotnet/sdk/2.1.302/Sdks
SDK Versions:
2.1.302
2.1.301
2.1.4
2.0.3
2.0.0
1.0.3
1.0.1
1.0.0-preview2-003156
MSBuild SDKs: /Library/Frameworks/Mono.framework/Versions/5.12.0/lib/mono/msbuild/15.0/bin/Sdks

=== Build Information ===

058cb01831cbafedd363c68e99e9b587db13a059

=== Operating System ===

Mac OS X 10.13.6
Darwin 17.7.0 Darwin Kernel Version 17.7.0
Thu Jun 21 22:53:14 PDT 2018
root:xnu-4570.71.2~1/RELEASE_X86_64 x86_64