Exclusive Nativization Method will nativize unselected struct blueprints

When the Project Nativization method is set to Exclusive, packaging the project will cause any struct blueprint (UUserDefinedStruct asset) to be nativized, without actually setting nativization on the struct blueprint itself.

Regression:
No - same behavior occurs in 4.17.2 (CL 3658906)

1. Open UE4 Editor (any project)
2. Right click in Content Browser and select Bluprints > Structure (CustomStruct)
3. Open Project Settings and search for "Nativization"
4. Set Blueprint Nativization Method to Exclusive
5. Package project
6. Navigate to ProjectName\Intermediate\Plugins\WindowsNoEditor\NativizedAssets\Source\NativizedAssets\Privte(or Public)

Result:
Noticed "CustomStruct_pf######.h / .cpp" exist in the public/private folders respectively

Expected:
Only assets specifically marked for nativization are included when method is set to Exclusive