Repro Steps:

1) Create a Page
2) Introduce a Rectangle to the Root Grid
3) Apply a Gradient as a Fill for the Rectangle.
4) Using the 3-Dot menu on the Fill Property in the Properties Panel, select 'Convert to Resource'. This rectangle is now using a Dynamic Resource for the Fill.
5) From either the Stage, or the Navigator, right-click on the Rectangle Shape, and navigate to the 'Path' submenu, then select 'Convert to Path'.

Observe the error indicating that the XAML has broken.
Observe how in the XAML Code, what used to be a functional DynamicResource for the Fill has transformed into a non-functional StaticResource which is unable to find the Gradient in the GlobalResources Dictionary.

Expected Results: Converting from a Shape to a Path doesn't break any Resources, and they are successfully converted over to a valid format in the process.