CppEditor: Extract some functions in AddIncludeForUndefinedIdentifier
CppEditor: Extract some functions in AddIncludeForUndefinedIdentifier

...to make the high level code path easier to follow.

Change-Id: If0ff9a15c9de399286e3a7f59a571949ca8f04de
Reviewed-by: Christian Stenger <accbb51712d7b9c4fb108439d01e716148e5f9e6@digia.com>

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