Emit a notifications when senderObject and signal are changed.

In order to properly use QSignalTransition object in QML we need to
know when these properties are changed.

Change-Id: I7ca318d50513086146b85eaeee4dabbcdef8c299
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
Reviewed-by: Kevin Funk <kevin.funk@kdab.com>
Emit a notifications when targetState and targetStates are changed.

In order to properly use QAbstractTransition object in QML we need to
know when these properties are changed.

Change-Id: I5449ecf3fce33e164f645d7263f21b20abfcd026
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
qHash overload for Q{Explicitly,}SharedDataPointer

Interestingly, before that patch this compiled fine:

  typedef Q{Explicitly,}SharedDataPointer<QSharedData> Ptr;
  Ptr p(new QSharedData);
  auto hash = qHash(p);

This was because both Q{Explicitly,}SharedDataPointer overload 'operator
bool()' => qHash(int) was accepted. This, however, doesn't make sense.

Someone should probably take care of applying the safe bool idiom to
these classes as well.

Change-Id: I8bb6b2aacaa6166da817a6f3847093fd20a05a67
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>