[PATCH 2/6] winmm: DriverCallback ignores a 0 CALLBACK_WINDOW.

[Joerg-Cyril.Hoehle at t-systems.com]

Hi,

any feedback on winmm:DriverCallback patches 2-6?

- Although I superseded patch 1/6, the others are unchanged,
 hence I did not resend them.

- I thought about merging patches 2+3+5 into one or two. After all,
 they all change the one tiny DriverCallback function.
 E.g. patch 2 fixes the corner case where Wine delivers a spurious
 message to the thread message queue, while patch 5 generalizes
 the behaviour that MS mentions (and I tested), i.e. ignore any 0 dwCallback.
 OTOH, split is split.

- It may seem weird to go to some effort to make DriverCallback
  return the exact same values as native *and* then change all
 drivers to ignore that value, so the patches may be considered
 superfluous. Yet we strive to be bug-compatible.

Regards,
 Jörg Höhle