Utils: Allow more finegrained subaspect ownership in AspectContainer

Currently this luckily conincides with the register/addAspect schism
but that's not necessarily true in the future.

Change-Id: I05a59d74182dbdf81193ebd790d6f9bab2d30439
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/projectexplorer/projectconfiguration.cpp

@@ -22,8 +22,6 @@ ProjectConfiguration::ProjectConfiguration(QObject *parent, Utils::Id id)
     : AspectContainer(parent)
     , m_id(id)
 {
-    setOwnsSubAspects(true);
-
     QTC_CHECK(parent);
     QTC_CHECK(id.isValid());
     setObjectName(id.toString());