Make GrDrawTarget::Caps ref counted and GrGLCaps derive from it.

Also rename GrDrawTarget::getCaps() -> GrDrawTarget::caps().
Review URL: https://codereview.chromium.org/12843026

git-svn-id: http://skia.googlecode.com/svn/trunk@8364 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrAAConvexPathRenderer.cpp b/src/gpu/GrAAConvexPathRenderer.cpp
index ebf2ea9..b4509b3 100644
--- a/src/gpu/GrAAConvexPathRenderer.cpp
+++ b/src/gpu/GrAAConvexPathRenderer.cpp
@@ -432,7 +432,7 @@
                                          const SkStrokeRec& stroke,
                                          const GrDrawTarget* target,
                                          bool antiAlias) const {
-    return (target->getCaps().shaderDerivativeSupport() && antiAlias &&
+    return (target->caps()->shaderDerivativeSupport() && antiAlias &&
             stroke.isFillStyle() && !path.isInverseFillType() && path.isConvex());
 }