Not including StarterContent/Templates prevents engine .cpp files from appearing in project VS

If either/both of the "Starter Content" or "Template and Feature Packs" checkbox's are not selected when installing/updating 4.12 from the Launcher, the engine .cpp files will not show up in Visual Studio for a code based project.

Regression:
Yes - .cpp files still appear in 4.11.2 with the checkboxes unchecked.

1. Open UE4Launcher
2. Click Dropdown button next to launch and select Options
3. Deselect Starter Content or Templates and Feature Packs and Apply
4. Launch the editor and create a code project
5. When VS opens, navigate the Solution Explorer to Engine->UE4->Source->Runtime->Core->Private->Math

Result:
No .cpp files are present in the folder

Expected:
Engine .cpp files appear even when not using Starter Content or project templates.