matching relative paths in the Locator does not work on windows

Assuming a project has multiple executables and each has a main.cpp its very hard to open the main.cpp from a particular executable in Creator on Windows even if the executables are in separate subfolders. On Linux specifying "<suffix-of-foldername>/main" in the locator allows to quickly filter the list to one or a few entries. This does not work on Windows no matter wether slash or backslash is used as separator.