Qbs: Fix memory leak in Qbs Project Manager
Qbs: Fix memory leak in Qbs Project Manager

Make sure the root node of the project tree is actually deleted.

Change-Id: Idf32460d7b5d0518da9536084cccb074638cfce3
Reviewed-by: Tobias Hunger <012f8d714267bccc9d4766fbeace9f175fcc70c4@digia.com>

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