Add a requiresVertexShader method to GrGLEffect

src/gpu/GrAAConvexPathRenderer.cpp

Index: src/gpu/GrAAConvexPathRenderer.cpp
diff --git a/src/gpu/GrAAConvexPathRenderer.cpp b/src/gpu/GrAAConvexPathRenderer.cpp
index e50e6b406eb0d276c6ad0cdb89ff0d899326bea7..f08e8f1bb020859d4d0eedf7f5d854f8c3046a0d 100644
--- a/src/gpu/GrAAConvexPathRenderer.cpp
+++ b/src/gpu/GrAAConvexPathRenderer.cpp
@@ -524,6 +524,8 @@ public:
         GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&)
             : INHERITED (factory) {}
 
+        virtual bool requiresVertexShader(const GrDrawEffect&) const { return true; }
+
         virtual void emitCode(GrGLShaderBuilder* builder,
                               const GrDrawEffect& drawEffect,
                               EffectKey key,