Re-generation of the Makefile depends on a correctly set up
QMAKE_INTERNAL_INCLUDED_FILES variable. In debug_and_release builds
this variable is set up for Makefile.Debug and Makefile.Release, but
not for the meta Makefile. However, that's where the Makefile
re-generation target is located.
We now collect the contents of QMAKE_INTERNAL_INCLUDED_FILES for
Makefile.Debug/Release and use that for the meta Makefile.
Fixes: QTBUG-13334
Change-Id: I6124a91447d5c54d51680e23570c4e97f44e6a73
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
97d6517114