C++: Improve calculation of function argument count.
C++: Improve calculation of function argument count.

Reuse Function::argumentCount instead of reimplementing it.

Change-Id: I05ba2dbee087e5dfd53c7af3ec94d214f6e37a54
Reviewed-by: Leandro T. C. Melo <8f144cd741810d8c7b648cacf5b9b2f4e2ebcc1b@nokia.com>

Distrotech/qtcreator,Distrotech/qtcreator,kuba1/qtcreator,azat/qtcreator,syntheticpp/qt-creator,bakaiadam/collaborative_qt_creator,danimo/qt-creator,richardmg/qtcreator,colede/qtcreator,danimo/qt-creator,kuba1/qtcreator,KDE/android-qt-creator,xianian/qt-creator,KDAB/KDAB-Creator,azat/qtcreator,syntheticpp/qt-creator,richardmg/qtcreator,azat/qtcreator,martyone/sailfish-qtcreator,omniacreator/qtcreator,amyvmiwei/qt-creator,richardmg/qtcreator,azat/qtcreator,xianian/qt-creator,farseerri/git_code,darksylinc/qt-creator,AltarBeastiful/qt-creator,ostash/qt-creator-i18n-uk,colede/qtcreator,AltarBeastiful/qt-creator,Distrotech/qtcreator,KDAB/KDAB-Creator,AltarBeastiful/qt-creator,farseerri/git_code,AltarBeastiful/qt-creator,hdweiss/qt-creator-visualizer,bakaiadam/collaborative_qt_creator,maui-packages/qt-creator,xianian/qt-creator,syntheticpp/qt-creator,darksylinc/qt-creator,duythanhphan/qt-creator,hdweiss/qt-creator-visualizer,kuba1/qtcreator,syntheticpp/qt-creator,amyvmiwei/qt-creator,xianian/qt-creator,danimo/qt-creator,amyvmiwei/qt-creator,ostash/qt-creator-i18n-uk,ostash/qt-creator-i18n-uk,darksylinc/qt-creator,darksylinc/qt-creator,kuba1/qtcreator,kuba1/qtcreator,maui-packages/qt-creator,bakaiadam/collaborative_qt_creator,KDE/android-qt-creator,KDE/android-qt-creator,omniacreator/qtcreator,amyvmiwei/qt-creator,jonnor/qt-creator,jonnor/qt-creator,duythanhphan/qt-creator,KDAB/KDAB-Creator,danimo/qt-creator,Distrotech/qtcreator,azat/qtcreator,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,martyone/sailfish-qtcreator,omniacreator/qtcreator,bakaiadam/collaborative_qt_creator,danimo/qt-creator,maui-packages/qt-creator,danimo/qt-creator,ostash/qt-creator-i18n-uk,farseerri/git_code,martyone/sailfish-qtcreator,martyone/sailfish-qtcreator,danimo/qt-creator,kuba1/qtcreator,omniacreator/qtcreator,malikcjm/qtcreator,kuba1/qtcreator,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,bakaiadam/collaborative_qt_creator,amyvmiwei/qt-creator,AltarBeastiful/qt-creator,darksylinc/qt-creator,colede/qtcreator,hdweiss/qt-creator-visualizer,richardmg/qtcreator,amyvmiwei/qt-creator,colede/qtcreator,colede/qtcreator,hdweiss/qt-creator-visualizer,KDE/android-qt-creator,farseerri/git_code,farseerri/git_code,jonnor/qt-creator,KDE/android-qt-creator,duythanhphan/qt-creator,AltarBeastiful/qt-creator,syntheticpp/qt-creator,danimo/qt-creator,darksylinc/qt-creator,ostash/qt-creator-i18n-uk,maui-packages/qt-creator,farseerri/git_code,Distrotech/qtcreator,KDAB/KDAB-Creator,malikcjm/qtcreator,xianian/qt-creator,KDAB/KDAB-Creator,malikcjm/qtcreator,darksylinc/qt-creator,martyone/sailfish-qtcreator,bakaiadam/collaborative_qt_creator,martyone/sailfish-qtcreator,duythanhphan/qt-creator,Distrotech/qtcreator,duythanhphan/qt-creator,jonnor/qt-creator,duythanhphan/qt-creator,bakaiadam/collaborative_qt_creator,omniacreator/qtcreator,jonnor/qt-creator,xianian/qt-creator,xianian/qt-creator,syntheticpp/qt-creator,omniacreator/qtcreator,KDE/android-qt-creator,maui-packages/qt-creator,richardmg/qtcreator,KDE/android-qt-creator,syntheticpp/qt-creator,richardmg/qtcreator,martyone/sailfish-qtcreator,AltarBeastiful/qt-creator,malikcjm/qtcreator,ostash/qt-creator-i18n-uk,malikcjm/qtcreator,maui-packages/qt-creator,colede/qtcreator,farseerri/git_code,omniacreator/qtcreator,hdweiss/qt-creator-visualizer,amyvmiwei/qt-creator,malikcjm/qtcreator,ostash/qt-creator-i18n-uk,richardmg/qtcreator,kuba1/qtcreator,jonnor/qt-creator,Distrotech/qtcreator,KDAB/KDAB-Creator,danimo/qt-creator,KDE/android-qt-creator,azat/qtcreator,xianian/qt-creator,malikcjm/qtcreator,colede/qtcreator,hdweiss/qt-creator-visualizer,farseerri/git_code,xianian/qt-creator,darksylinc/qt-creator,maui-packages/qt-creator,kuba1/qtcreator,duythanhphan/qt-creator