C++: fix the quick-exit for already parsed files.
C++: fix the quick-exit for already parsed files.

When the preprocessor is asked to process a file which it has already
seen before, it can skip it, but it still has to add the file to the
list of included files for the current document.

Task-number: QTCREATORBUG-9107
Change-Id: I30cac61c1da20da7fe925168ecccb429584e9746
Reviewed-by: Nikolai Kosjar <9571db158ca61a0d070db010803474231fa0cbab@digia.com>

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