QmakeProject: Fix crash on unloading projects
QmakeProject: Fix crash on unloading projects

The QmakeVfs needs to be deleted after all evaluations have been
canceled. Those are canceled in the destructors of the nodes, so
delete the nodes before deleting m_qmakeVfs

Task-number: QTCREATORBUG-13421
Change-Id: I5883f5b2daa6a13ef4facf9b9dccc125a069df94
Reviewed-by: Orgad Shaneh <2b010cbad792a0c0a8175f752f93f83941fc6bc1@gmail.com>

kuba1/qtcreator,martyone/sailfish-qtcreator,danimo/qt-creator,danimo/qt-creator,martyone/sailfish-qtcreator,danimo/qt-creator,Distrotech/qtcreator,martyone/sailfish-qtcreator,danimo/qt-creator,Distrotech/qtcreator,kuba1/qtcreator,farseerri/git_code,farseerri/git_code,amyvmiwei/qt-creator,amyvmiwei/qt-creator,farseerri/git_code,xianian/qt-creator,kuba1/qtcreator,xianian/qt-creator,AltarBeastiful/qt-creator,farseerri/git_code,Distrotech/qtcreator,amyvmiwei/qt-creator,martyone/sailfish-qtcreator,kuba1/qtcreator,Distrotech/qtcreator,martyone/sailfish-qtcreator,amyvmiwei/qt-creator,danimo/qt-creator,xianian/qt-creator,farseerri/git_code,danimo/qt-creator,martyone/sailfish-qtcreator,martyone/sailfish-qtcreator,farseerri/git_code,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,kuba1/qtcreator,danimo/qt-creator,Distrotech/qtcreator,amyvmiwei/qt-creator,danimo/qt-creator,farseerri/git_code,xianian/qt-creator,amyvmiwei/qt-creator,kuba1/qtcreator,xianian/qt-creator,kuba1/qtcreator,AltarBeastiful/qt-creator,xianian/qt-creator,xianian/qt-creator,AltarBeastiful/qt-creator,amyvmiwei/qt-creator,AltarBeastiful/qt-creator,farseerri/git_code,martyone/sailfish-qtcreator,AltarBeastiful/qt-creator,xianian/qt-creator,Distrotech/qtcreator,AltarBeastiful/qt-creator,AltarBeastiful/qt-creator,kuba1/qtcreator,danimo/qt-creator,amyvmiwei/qt-creator,Distrotech/qtcreator,kuba1/qtcreator,xianian/qt-creator