More non_exhaustive (#6408)

Fixes #4673


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Author: Manishearth

components/time/src/zone/mod.rs

@@ -131,7 +131,7 @@ pub mod models {
     /// A time zone containing a time zone ID and optional offset.
     #[derive(Debug, PartialEq, Eq)]
     #[non_exhaustive]
-    pub enum Base {}
+    pub struct Base;
 
     impl private::Sealed for Base {}
     impl TimeZoneModel for Base {
@@ -142,7 +142,7 @@ pub mod models {
     /// A time zone containing a time zone ID, optional offset, and local time.
     #[derive(Debug, PartialEq, Eq)]
     #[non_exhaustive]
-    pub enum AtTime {}
+    pub struct AtTime;
 
     impl private::Sealed for AtTime {}
     impl TimeZoneModel for AtTime {
@@ -153,7 +153,7 @@ pub mod models {
     /// A time zone containing a time zone ID, optional offset, local time, and zone variant.
     #[derive(Debug, PartialEq, Eq)]
     #[non_exhaustive]
-    pub enum Full {}
+    pub struct Full;
 
     impl private::Sealed for Full {}
     impl TimeZoneModel for Full {

ffi/capi/src/timezone.rs

@@ -76,9 +76,9 @@ pub mod ffi {
 
     #[diplomat::opaque]
     #[diplomat::rust_link(icu::time::TimeZoneInfo, Struct)]
-    #[diplomat::rust_link(icu::time::zone::models::AtTime, Enum, hidden)]
-    #[diplomat::rust_link(icu::time::zone::models::Base, Enum, hidden)]
-    #[diplomat::rust_link(icu::time::zone::models::Full, Enum, hidden)]
+    #[diplomat::rust_link(icu::time::zone::models::AtTime, Struct, hidden)]
+    #[diplomat::rust_link(icu::time::zone::models::Base, Struct, hidden)]
+    #[diplomat::rust_link(icu::time::zone::models::Full, Struct, hidden)]
     pub struct TimeZoneInfo {
         pub(crate) time_zone_id: icu_time::TimeZone,
         pub(crate) offset: Option<icu_time::zone::UtcOffset>,