Wizards: Add File to Empty qmake Project does not take projects path into account [Regression]

Steps to reproduce:

• create an Empty qmake Project using the wizard
• add a C++ file to this project using the wizard (used main.cpp)
  • inside the wizard check the Location page (where you give the file a name)

Current result:

• default path for the location of the file is the path from where QC has been started

Expected result:

• default path for the location should be the path of the current active project

Note: this works fine on 3.3 branch.