Rightclicking on brush selection button with preset active is surprisingly useless

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Supposing you have a preset type brush selected -- like a 3x3 diamond, say. If 
you rightclick on the brush selector, it makes the brush into something useless 
(the resultant brush has no solid areas, and therefore no effect).

IMO the correct behaviour would be to convert the brush to a normal 'grabbed' 
type brush with (current BGcolor) as the background, and the first non-BGcolor 
slot in the palette as the 'solid' parts of the brush.
(and then, of course, set the brush rendering mode to monochrome)

Original issue reported on code.google.com by fintic...@gmail.com on 17 Oct 2013 at 12:34