dinput: Added a check for NULL callback in EnumDevices.

[Vitaliy Margolen]

On 06/04/2011 01:32 PM, Lucas Zawacki wrote:
>> Sometimes apps depend on the crash.  Since your change comes with a
>> test case, it looks reasonable to me, although you might check the
>> specific HRESULT rather than just FAILED.
>
> Exactly, it's not a crash on Windows. I'll resend it with an explicit test.
>
> I was thinking of this more as "janitorial" work as opposed to fixing
> a buggy app, maybe my comment worded it badly.

AJ was explicit about such checks: unless you have an application that 
breaks because of this don't add any null checks. They needlessly slowdown 
Wine. And won't guard you against invalid pointer anyway.

Vitaliy.