Code review comment for lp://staging/~smspillaz/compiz-core/fix_894688

>> ln 214 - Why not write this as:
>>
>> cScreen->damageRegion(oldGeometry + newGeometry);

> fixed

Actually, there's no operator+ defined in CompRect which returns a region, and I'm not really sure if I want to introduce a cyclic dependency like that. So I think the explicit conversion is better off for now.