debugger: do not write the 'all' (-1) threadspec to the session file
debugger: do not write the 'all' (-1) threadspec to the session file

This confuses 2.1 which uses 0 as 'all' value.

syntheticpp/qt-creator,bakaiadam/collaborative_qt_creator,azat/qtcreator,Distrotech/qtcreator,renatofilho/QtCreator,jonnor/qt-creator,darksylinc/qt-creator,azat/qtcreator,Distrotech/qtcreator,renatofilho/QtCreator,KDE/android-qt-creator,martyone/sailfish-qtcreator,azat/qtcreator,colede/qtcreator,darksylinc/qt-creator,KDAB/KDAB-Creator,darksylinc/qt-creator,bakaiadam/collaborative_qt_creator,hdweiss/qt-creator-visualizer,ostash/qt-creator-i18n-uk,KDE/android-qt-creator,syntheticpp/qt-creator,malikcjm/qtcreator,duythanhphan/qt-creator,amyvmiwei/qt-creator,richardmg/qtcreator,KDE/android-qt-creator,farseerri/git_code,yinyunqiao/qtcreator,danimo/qt-creator,sandsmark/qtcreator-minimap,danimo/qt-creator,dmik/qt-creator-os2,azat/qtcreator,Distrotech/qtcreator,syntheticpp/qt-creator,pcacjr/qt-creator,richardmg/qtcreator,danimo/qt-creator,maui-packages/qt-creator,jonnor/qt-creator,AltarBeastiful/qt-creator,amyvmiwei/qt-creator,maui-packages/qt-creator,jonnor/qt-creator,bakaiadam/collaborative_qt_creator,omniacreator/qtcreator,amyvmiwei/qt-creator,renatofilho/QtCreator,martyone/sailfish-qtcreator,duythanhphan/qt-creator,azat/qtcreator,duythanhphan/qt-creator,danimo/qt-creator,KDE/android-qt-creator,yinyunqiao/qtcreator,dmik/qt-creator-os2,renatofilho/QtCreator,KDAB/KDAB-Creator,maui-packages/qt-creator,colede/qtcreator,renatofilho/QtCreator,dmik/qt-creator-os2,kuba1/qtcreator,duythanhphan/qt-creator,hdweiss/qt-creator-visualizer,richardmg/qtcreator,xianian/qt-creator,martyone/sailfish-qtcreator,richardmg/qtcreator,martyone/sailfish-qtcreator,farseerri/git_code,kuba1/qtcreator,hdweiss/qt-creator-visualizer,danimo/qt-creator,ostash/qt-creator-i18n-uk,richardmg/qtcreator,ostash/qt-creator-i18n-uk,colede/qtcreator,dmik/qt-creator-os2,amyvmiwei/qt-creator,omniacreator/qtcreator,bakaiadam/collaborative_qt_creator,dmik/qt-creator-os2,jonnor/qt-creator,syntheticpp/qt-creator,xianian/qt-creator,farseerri/git_code,kuba1/qtcreator,malikcjm/qtcreator,yinyunqiao/qtcreator,bakaiadam/collaborative_qt_creator,duythanhphan/qt-creator,KDE/android-qt-creator,kuba1/qtcreator,yinyunqiao/qtcreator,yinyunqiao/qtcreator,renatofilho/QtCreator,Distrotech/qtcreator,malikcjm/qtcreator,kuba1/qtcreator,kuba1/qtcreator,syntheticpp/qt-creator,KDE/android-qt-creator,maui-packages/qt-creator,ostash/qt-creator-i18n-uk,maui-packages/qt-creator,AltarBeastiful/qt-creator,xianian/qt-creator,kuba1/qtcreator,AltarBeastiful/qt-creator,hdweiss/qt-creator-visualizer,jonnor/qt-creator,farseerri/git_code,omniacreator/qtcreator,sandsmark/qtcreator-minimap,omniacreator/qtcreator,colede/qtcreator,ostash/qt-creator-i18n-uk,duythanhphan/qt-creator,kuba1/qtcreator,farseerri/git_code,xianian/qt-creator,KDE/android-qt-creator,amyvmiwei/qt-creator,KDE/android-qt-creator,hdweiss/qt-creator-visualizer,kuba1/qtcreator,amyvmiwei/qt-creator,AltarBeastiful/qt-creator,omniacreator/qtcreator,malikcjm/qtcreator,pcacjr/qt-creator,martyone/sailfish-qtcreator,darksylinc/qt-creator,duythanhphan/qt-creator,pcacjr/qt-creator,amyvmiwei/qt-creator,colede/qtcreator,malikcjm/qtcreator,omniacreator/qtcreator,ostash/qt-creator-i18n-uk,maui-packages/qt-creator,colede/qtcreator,yinyunqiao/qtcreator,azat/qtcreator,sandsmark/qtcreator-minimap,KDAB/KDAB-Creator,danimo/qt-creator,farseerri/git_code,syntheticpp/qt-creator,xianian/qt-creator,farseerri/git_code,sandsmark/qtcreator-minimap,danimo/qt-creator,martyone/sailfish-qtcreator,Distrotech/qtcreator,omniacreator/qtcreator,sandsmark/qtcreator-minimap,hdweiss/qt-creator-visualizer,AltarBeastiful/qt-creator,xianian/qt-creator,Distrotech/qtcreator,pcacjr/qt-creator,danimo/qt-creator,AltarBeastiful/qt-creator,syntheticpp/qt-creator,AltarBeastiful/qt-creator,pcacjr/qt-creator,xianian/qt-creator,yinyunqiao/qtcreator,darksylinc/qt-creator,martyone/sailfish-qtcreator,pcacjr/qt-creator,pcacjr/qt-creator,dmik/qt-creator-os2,farseerri/git_code,AltarBeastiful/qt-creator,dmik/qt-creator-os2,malikcjm/qtcreator,malikcjm/qtcreator,bakaiadam/collaborative_qt_creator,KDAB/KDAB-Creator,bakaiadam/collaborative_qt_creator,KDAB/KDAB-Creator,xianian/qt-creator,ostash/qt-creator-i18n-uk,KDAB/KDAB-Creator,richardmg/qtcreator,darksylinc/qt-creator,colede/qtcreator,sandsmark/qtcreator-minimap,xianian/qt-creator,danimo/qt-creator,jonnor/qt-creator,martyone/sailfish-qtcreator,darksylinc/qt-creator,martyone/sailfish-qtcreator,darksylinc/qt-creator,amyvmiwei/qt-creator,maui-packages/qt-creator,Distrotech/qtcreator,richardmg/qtcreator