rem: void mergePer( Todo* const dest, const Todo* const src) { dest->setPercentComplete( src->percentComplete() ); }
add: static void mergePer( Todo* const dest, const Todo* const src) { dest->setPercentComplete( src->percentComplete() ); }
context:     void mergePer( Todo* const dest, const Todo* const src)    {        dest->setPercentComplete( src->percentComplete() );    }