[lazarus] win32 interface: CheckListBox memleak.

[Micha Nelissen]

Vincent Snijders wrote:

> I investigated why sometimes the ItemRecords of a checklistbox aren't
> freeed. What happens is, that the LCL sends a LM_DESTROY message to the
> interface for the checklistbox. The interface removes the Lazarus
> property from the checklistbox window. Therefore when the windows is
> destroyed and the WM_DESTROY message is received, the owner object is
> nil and we don't know what (type) the original lcl object was.
> 
> I propose that we remove the line (around line 583 of win32object.inc)
>   RemoveProp(Handle, 'Lazarus');
> 
> Then when the WM_DESTROY message is received in the windows procedure,
> there is still a owner object. 
> 
> The Lazarus property will be removed by the enumprops call later in the
> WM_DESTROY handling code.

Good idea, applied.

Thanks,

Micha.