FakeVim: Prevent crash in scrollToLine with Qt 4
FakeVim: Prevent crash in scrollToLine with Qt 4

There seem to be cases where QTextLines::isValid() returns true but
its lines_ are empty.

Change-Id: Ia4b9a66aec8d10754f7ff7dd0c90e7295e2a2220
Reviewed-by: hjk <f81b91af79013637d070c18d38a75b90eaae8ba3@nokiamail.com>

amyvmiwei/qt-creator,danimo/qt-creator,xianian/qt-creator,martyone/sailfish-qtcreator,farseerri/git_code,kuba1/qtcreator,danimo/qt-creator,kuba1/qtcreator,xianian/qt-creator,darksylinc/qt-creator,amyvmiwei/qt-creator,Distrotech/qtcreator,maui-packages/qt-creator,AltarBeastiful/qt-creator,colede/qtcreator,AltarBeastiful/qt-creator,omniacreator/qtcreator,maui-packages/qt-creator,maui-packages/qt-creator,amyvmiwei/qt-creator,colede/qtcreator,Distrotech/qtcreator,colede/qtcreator,martyone/sailfish-qtcreator,darksylinc/qt-creator,amyvmiwei/qt-creator,darksylinc/qt-creator,amyvmiwei/qt-creator,xianian/qt-creator,colede/qtcreator,farseerri/git_code,xianian/qt-creator,maui-packages/qt-creator,kuba1/qtcreator,Distrotech/qtcreator,omniacreator/qtcreator,farseerri/git_code,danimo/qt-creator,danimo/qt-creator,omniacreator/qtcreator,amyvmiwei/qt-creator,farseerri/git_code,martyone/sailfish-qtcreator,omniacreator/qtcreator,danimo/qt-creator,xianian/qt-creator,AltarBeastiful/qt-creator,maui-packages/qt-creator,farseerri/git_code,xianian/qt-creator,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,AltarBeastiful/qt-creator,maui-packages/qt-creator,martyone/sailfish-qtcreator,darksylinc/qt-creator,farseerri/git_code,danimo/qt-creator,omniacreator/qtcreator,Distrotech/qtcreator,xianian/qt-creator,darksylinc/qt-creator,danimo/qt-creator,Distrotech/qtcreator,omniacreator/qtcreator,colede/qtcreator,darksylinc/qt-creator,farseerri/git_code,colede/qtcreator,farseerri/git_code,amyvmiwei/qt-creator,martyone/sailfish-qtcreator,darksylinc/qt-creator,martyone/sailfish-qtcreator,martyone/sailfish-qtcreator,kuba1/qtcreator,Distrotech/qtcreator,amyvmiwei/qt-creator,AltarBeastiful/qt-creator,danimo/qt-creator,Distrotech/qtcreator,omniacreator/qtcreator,AltarBeastiful/qt-creator,kuba1/qtcreator,kuba1/qtcreator,martyone/sailfish-qtcreator,kuba1/qtcreator,darksylinc/qt-creator,AltarBeastiful/qt-creator,xianian/qt-creator,danimo/qt-creator,kuba1/qtcreator,maui-packages/qt-creator,xianian/qt-creator,kuba1/qtcreator,colede/qtcreator