feat(halo2_proofs): add bytes_length_including_cs()

`bytes_length()` is better to remain the same.

halo2_proofs/src/plonk.rs

@@ -187,10 +187,15 @@ impl<C: CurveAffine> VerifyingKey<C>
 where
     C::ScalarExt: FromUniformBytes<64>,
 {
-    fn bytes_length(&self) -> usize {
+    pub fn bytes_length_including_cs(&self) -> usize {
         8 + (self.fixed_commitments.len() * C::default().to_bytes().as_ref().len())
             + self.permutation.bytes_length()
             + self.cs.bytes_length()
+    }
+
+    fn bytes_length(&self) -> usize {
+        8 + (self.fixed_commitments.len() * C::default().to_bytes().as_ref().len())
+            + self.permutation.bytes_length()
         // scroll/halo2: we don’t need to store
         // + self.selectors.len()
         //     * (self
@@ -323,6 +328,18 @@ where
         &self.vk
     }
 
+    /// Gets the total number of bytes in the serialization of `self` including constraint system
+    pub fn bytes_length_including_cs(&self) -> usize {
+        let scalar_len: usize = C::Scalar::default().to_repr().as_ref().len();
+        self.vk.bytes_length_including_cs()
+                + 12
+                + scalar_len * (self.l0.len() + self.l_last.len() + self.l_active_row.len())
+                + polynomial_slice_byte_length(&self.fixed_values)
+                + polynomial_slice_byte_length(&self.fixed_polys)
+                //+ polynomial_slice_byte_length(&self.fixed_cosets)
+                + self.permutation.bytes_length()
+    }
+
     /// Gets the total number of bytes in the serialization of `self`
     fn bytes_length(&self) -> usize {
         let scalar_len = C::Scalar::default().to_repr().as_ref().len();