Auto-detection of toolchain for auto-detected kit does not work

1. Have MSVC compiler and CDB debugger installed.
2. Have a Qt version built with MinGW and a matching MinGW compiler in PATH variable.
3. Delete Creator's settings from %APPDATA%.
4. Start Creator.
5. Go to "Tools" -> "Options..." -> "Build & Run" -> "Kits".
   There will be an auto-detected Kit using the MinGW Qt version. For this Kit, the MSVC compiler and the CDB debugger are set. Creator even shows a warning that these don't match.

When auto-detecting Kits, Creator should also auto-detect the matching compiler and debugger. In the above example, MinGW and gdb should be set for the kit.