The pch creation so far used signal and slots but there was no explicit
pipeline. This patch is introducing the same architecture like the
refactoring plugin. It is filtering out older project parts from the
pipeline.
Change-Id: Iaa6bd2ca1272231b97ebe1f5f7b2ce8e43bc590c
Task-number: QTCREATORBUG-21111
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>
The project parts are now first used by the pch manager and then notified
by the pch manager to the refactoring plugin.
Change-Id: I88074d8891cd0de9721497bbafee0deffc0b6339
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>