make vtr_strong operators noexcept

Author: soheilshahrouz

libs/libvtrutil/src/vtr_strong_id.h

@@ -160,10 +160,10 @@ class StrongId;
  * friend them
  */
 template<typename tag, typename T, T sentinel>
-constexpr bool operator==(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs);
+constexpr bool operator==(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs) noexcept;
 
 template<typename tag, typename T, T sentinel>
-constexpr bool operator!=(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs);
+constexpr bool operator!=(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs) noexcept;
 
 template<typename tag, typename T, T sentinel>
 constexpr bool operator<(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs) noexcept;
@@ -228,13 +228,13 @@ class StrongId {
 
 ///@brief == operator
 template<typename tag, typename T, T sentinel>
-constexpr bool operator==(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs) {
+constexpr bool operator==(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs) noexcept {
     return lhs.id_ == rhs.id_;
 }
 
 ///@brief != operator
 template<typename tag, typename T, T sentinel>
-constexpr bool operator!=(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs) {
+constexpr bool operator!=(const StrongId<tag, T, sentinel>& lhs, const StrongId<tag, T, sentinel>& rhs) noexcept {
     return !(lhs == rhs);
 }