Hot Reload wipes all elements of UProperty TArrays in Blueprint subclasses

Hot reloading a change that affects a class that contains a TArray UProperty will wipe all of the array elements of any Blueprint subclasses of that class.

Regression?: Yes
This does not occur in 4.17.2

1. Download the attached project, Generate Project Files, compile and open the project
2. Select the instance of ValueTrackerBP in the level and notice the elements of the TransformsArray
3. Open PropertyError.sln in Visual Studio
4. Uncomment the property on lines 29 and 30
5. Compile
6. After the compilation finishes and the hot reload is successful, check the elements of the TransformsArray on the ValueTrackerBP instance in the level
   Result: The elements have been wiped
   Expected: The elements remain