I think citydlg.h was missed from the commit to svn (r21586), although it's in the attached patches.

With citydlg.h from file #16129, it builds and runs for me.

Generally each patch should contain just one change, and no unrelated things. No need to split this patch, but keep it in mind when writing future patches.

Changes in attached version:

- Minor style corrections
- Replaced includes in citydlg.h with class forward declarations as only pointers are needed
- Corrected a couple of errors in translatable strings
- Use population_to_text() instead of just adding string "000"

(file #16129)

I just noticed that translated showed strings are bad, but addding
QTextCodec::setCodecForCStrings(QTextCodec::codecForName("UTF-8"));
in main() will fix it - there is a lot of strings to update cause small/big letter mismatch and many of them are not translated due to that )