make pathrenderers release their geometry before returning

[bsalomon, 2012-03-07 19:00:57]

The GrPathRenderer interface is back to a one-shot model now that the
supersampling code is removed. But the GrPathRenderer subclasses aren't
releasing their geometry after they draw. It gets released on the next draw but
it doesn't play nicely with changes that would draw the paths into a
GrInOrderDrawBuffer. GrPathRenderers, release your geometry!

[TomH, 2012-03-07 19:05:23]

LGTM. I'd like to understand "one-shot model", however.

http://codereview.appspot.com/5753073/diff/1/src/gpu/GrDefaultPathRenderer.cpp
File src/gpu/GrDefaultPathRenderer.cpp (right):

http://codereview.appspot.com/5753073/diff/1/src/gpu/GrDefaultPathRenderer.cp...
src/gpu/GrDefaultPathRenderer.cpp:248: base =
reinterpret_cast<GrPoint*>(arg->vertices());
Nit: is it worth initializing these immediately on declaration?

[bsalomon, 2012-03-07 19:15:57]

Committed w/ nit fix at 3335. (One-shot means drawPath() takes a path param,
draws it, forgets it. The interface used to allow setPath(), drawPath(),
drawPath(), ... , clearPath())