Revert "work around with QTBUG-43073"
Revert "work around with QTBUG-43073"

it is fixed in Qt 5.4.1

This reverts commit 05bd779925bbe277bf68146880cdf9fe55f31ddc.

lucius-feng/seafile-client,haiwen/seafile-client,daodaoliang/seafile-client,daodaoliang/seafile-client,wgaalves/seafile-client,losingle/seafile-client,lucius-feng/seafile-client,losingle/seafile-client,wgaalves/seafile-client,daodaoliang/seafile-client,daodaoliang/seafile-client,losingle/seafile-client,haiwen/seafile-client,lucius-feng/seafile-client,wgaalves/seafile-client,haiwen/seafile-client,losingle/seafile-client,wgaalves/seafile-client,haiwen/seafile-client,lucius-feng/seafile-client