Test factory uses the inorder draw buffer

BUG=skia:

Review URL: https://codereview.chromium.org/696353002
diff --git a/gm/convexpolyeffect.cpp b/gm/convexpolyeffect.cpp
index e567208..b4206d2 100644
--- a/gm/convexpolyeffect.cpp
+++ b/gm/convexpolyeffect.cpp
@@ -137,14 +137,18 @@
                 drawState->setRenderTarget(rt);
                 drawState->setColor(0xff000000);
 
-                SkPoint verts[4];
+                // TODO hack
+                GrDrawTarget::AutoReleaseGeometry geo(tt.target(), 4, 0);
+                SkPoint* verts = reinterpret_cast<SkPoint*>(geo.vertices());
+
+                //SkPoint verts[4];
                 SkRect bounds = p.getBounds();
                 // Make sure any artifacts around the exterior of path are visible by using overly
                 // conservative bounding geometry.
                 bounds.outset(5.f, 5.f);
                 bounds.toQuad(verts);
 
-                tt.target()->setVertexSourceToArray(verts, 4);
+                //tt.target()->setVertexSourceToArray(verts, 4);
                 tt.target()->setIndexSourceToBuffer(context->getQuadIndexBuffer());
                 tt.target()->drawIndexed(kTriangleFan_GrPrimitiveType, 0, 0, 4, 6);
 
@@ -191,12 +195,16 @@
                 drawState->setRenderTarget(rt);
                 drawState->setColor(0xff000000);
 
-                SkPoint verts[4];
+                // TODO hack
+                GrDrawTarget::AutoReleaseGeometry geo(tt.target(), 4, 0);
+                SkPoint* verts = reinterpret_cast<SkPoint*>(geo.vertices());
+
+                //SkPoint verts[4];
                 SkRect bounds = rect;
                 bounds.outset(5.f, 5.f);
                 bounds.toQuad(verts);
 
-                tt.target()->setVertexSourceToArray(verts, 4);
+                //tt.target()->setVertexSourceToArray(verts, 4);
                 tt.target()->setIndexSourceToBuffer(context->getQuadIndexBuffer());
                 tt.target()->drawIndexed(kTriangleFan_GrPrimitiveType, 0, 0, 4, 6);