Stylesheet: Fix size specified in QToolbar::handle
Stylesheet: Fix size specified in QToolbar::handle

Regression since f0243e70e05a3368582fd0478d840096d6b60c3f
We added a new rule (SE_ToolBarHandle) and the baseStyle was calling
pixelMetric(PM_ToolBarHandleExtent) on itself, bypassing the QStyleSheetStyle

Reviewed-by: Thierry
Task-number: QTBUG-8348

igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt