Describe the bug

DataGrid RowDetails not changing theme at runtime

Steps to Reproduce

Steps to reproduce the behavior:

1. Just add a DataGrid to a project and set the RowDetailsVisibilityMode to VisibleWhenSelected in order to observe the issue.
2. Add a button with a Click event to be able to change the app theme. RequestedTheme = ElementTheme.Dark or RequestedTheme = ElementTheme.Light will do the trick.
3. As yo can see, the background of the RowDetail did not change.

Expected behavior

See some change according with the theme color.

Screenshots

Environment

NuGet Package(s):  
`Microsoft.Toolkit.Uwp.UI.Controls`
`Microsoft.Toolkit.Uwp.UI.Controls.DataGrid`

Package Version(s):  
6.0 (Both)

Windows 10 Build Number:
Windows 10, Version 1909, Build 18363.836

App min and target version:
- [ ] May 2019 Update (18362)


Device form factor:
Desktop

Visual Studio 
2019 (version: 16.5.5) 

Additional context

I've noticed some issues like TitleBar color not change even when I use var titleBar = ApplicationView.GetForCurrentView().TitleBar; and change the properties of it (I asked on Stack Overflow about that and some people can successfully change the titlebar color with my exact code). I do not know if that can be related.