Qmake project: HEADERS are not sources
Qmake project: HEADERS are not sources

Fine tune the extra compilers support to know that we already show
headers in a separate category. HEADERS is the input to the moc
extra compiler.

Task-number: QTCREATORBUG-11459
Change-Id: I60e9c6b9eb2d55b7a0b02b5f63280b6268c42704
Reviewed-by: Oswald Buddenhagen <6a8868beda3e139b5ac22b2534a23d3e6ba81819@digia.com>

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