Add ES 3.0 fallback for instanced rendering

src/gpu/instanced/GLInstancedRendering.h

Index: src/gpu/instanced/GLInstancedRendering.h
diff --git a/src/gpu/instanced/GLInstancedRendering.h b/src/gpu/instanced/GLInstancedRendering.h
index 4e17cb4535c7c9b1a509b93582dc5670199730b0..ce1638c7fc5b9db1c553b1714d0b3e02931e65b4 100644
--- a/src/gpu/instanced/GLInstancedRendering.h
+++ b/src/gpu/instanced/GLInstancedRendering.h
@@ -43,10 +43,8 @@ private:
     void flushInstanceAttribs(int baseInstance);
 
     struct GLDrawCmdInfo {
-        int fInstanceCount;
-#if GR_GL_LOG_INSTANCED_BATCHES
         IndexRange fGeometry;
-#endif
+        int fInstanceCount;
     };
 
     GrGLuint                              fVertexArrayID;