winex11.drv: Use IsRectEmpty() instead of open coding it.

[Ken Thomases]

On May 4, 2016, at 2:58 AM, Alexandre Julliard <julliard at winehq.org> wrote:
> 
> Michael Stefaniuc <mstefani at redhat.de> writes:
> 
>> @@ -134,7 +134,7 @@ static inline void reset_bounds( RECT *bounds )
>> 
>> static inline void add_bounds_rect( RECT *bounds, const RECT *rect )
>> {
>> -    if (rect->left >= rect->right || rect->top >= rect->bottom) return;
>> +    if (IsRectEmpty(rect)) return;
> 
> I'm not sure it's an improvement to add a function call in such a simple
> inline function.

All of these sorts of patches have made me wonder if these RECT-related utility functions shouldn't themselves be defined static inline in the headers (as well as having real versions for export).

-Ken