*.pro中：
DEFINES += _qt_msvc_2015
contains(DEFINES,_qt_msvc_2015){
QT += webengine
QT += webenginewidgets
}else{
message("static release version : webengine webenginewidgets not support")
}
源代码中:
#ifdef _qt_msvc_2015
#include <QWebEngineView>
#endif
...
#ifdef _qt_msvc_2015
QWebEngineView * widget_web;
#endif
