[cairo] CAIRO_OPERATOR_CLEAR is not limited by clipping.

[Thinker]

Thinker wrote:
> Hi All,
> 
> I had find that API reference tells us that CAIRO_OPERATOR_CLEAR is
> bounded.  It means CAIRO_OPERATOR_CLEAR is bounded by the mask.  It is
> affected clipping.  But, I found that clipping is not work for a
> CAIRO_OPERATOR_CLEAR  operator.  I had try it on FreeBSD with cairo-1.8.6,1.
> 
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Sorry!! It is my fail.  The problem is resolved.  Thank You!!