message: removed tag_byte methods and changed expects to Results where these methods were used in execution_results.rs
diff: @@ -185,12 +185,6 @@ impl ExecutionResult {
  &*EXECUTION_RESULT
  }
  - fn tag_byte(&self) -> u8 {
  - self.tag()
  - .to_u8()
  - .expect("ExecutionResultTag should be represented as u8")
  - }
  -
  fn tag(&self) -> ExecutionResultTag {
  match self {
  ExecutionResult::Failure {
  @@ -259,7 +253,8 @@ impl Distribution<ExecutionResult> for Standard {
  impl ToBytes for ExecutionResult {
  fn to_bytes(&self) -> Result<Vec<u8>, bytesrepr::Error> {
  let mut buffer = bytesrepr::allocate_buffer(self)?;
  - buffer.push(self.tag_byte());
  + let tag_byte = self.tag().to_u8().ok_or(bytesrepr::Error::Formatting)?;
  + buffer.push(tag_byte);
  match self {
  ExecutionResult::Failure {
  effect,
  @@ -442,12 +437,6 @@ pub enum OpKind {
  }
  impl OpKind {
  - fn tag_byte(&self) -> u8 {
  - self.tag()
  - .to_u8()
  - .expect("OpTag should be represented as u8")
  - }
  -
  fn tag(&self) -> OpTag {
  match self {
  OpKind::Read => OpTag::Read,
  @@ -460,7 +449,8 @@ impl OpKind {
  impl ToBytes for OpKind {
  fn to_bytes(&self) -> Result<Vec<u8>, bytesrepr::Error> {
  - self.tag_byte().to_bytes()
  + let tag_bytes = self.tag().to_u8().ok_or(bytesrepr::Error::Formatting)?;
  + tag_bytes.to_bytes()
  }
  fn serialized_length(&self) -> usize {
  @@ -559,12 +549,6 @@ pub enum Transform {
  }
  impl Transform {
  - fn tag_byte(&self) -> u8 {
  - self.tag()
  - .to_u8()
  - .expect("TransformTag should be representable as a u8")
  - }
  -
  fn tag(&self) -> TransformTag {
  match self {
  Transform::Identity => TransformTag::Identity,
  @@ -592,7 +576,8 @@ impl Transform {
  impl ToBytes for Transform {
  fn to_bytes(&self) -> Result<Vec<u8>, bytesrepr::Error> {
  let mut buffer = bytesrepr::allocate_buffer(self)?;
  - buffer.insert(0, self.tag_byte());
  + let tag_bytes = self.tag().to_u8().ok_or(bytesrepr::Error::Formatting)?;
  + buffer.insert(0, tag_bytes);
  match self {
  Transform::Identity => {}
  Transform::WriteCLValue(value) => {
  