upgpkg: firefox-syncstorage 0.21.1-1

upstream release
Thanks to Matthieu Valleton for contributing a patch to restore MariaDB compatibility

firefox-syncstorage/mariadb-compat.patch

@@ -0,0 +1,69 @@
+idiff --git a/syncstorage-mysql/src/diesel_ext.rs b/syncstorage-mysql/src/diesel_ext.rs
+index 18abb4a..fe52470 100644
+--- a/syncstorage-mysql/src/diesel_ext.rs
++++ b/syncstorage-mysql/src/diesel_ext.rs
+@@ -3,11 +3,43 @@ use std::{fmt::Debug, marker::PhantomData};
+ use diesel::{
+     backend::Backend,
+     insertable::CanInsertInSingleQuery,
++    mysql::Mysql,
+     query_builder::{AstPass, InsertStatement, QueryFragment, QueryId},
++    query_dsl::methods::LockingDsl,
+     result::QueryResult,
+     Expression, QuerySource, RunQueryDsl,
+ };
+
++/// Emit MySQL <= 5.7's `LOCK IN SHARE MODE`
++///
++/// MySQL 8 supports `FOR SHARE` as an alias (which diesel natively supports)
++pub trait LockInShareModeDsl {
++    type Output;
++
++    fn lock_in_share_mode(self) -> Self::Output;
++}
++
++impl<T> LockInShareModeDsl for T
++where
++    T: LockingDsl<LockInShareMode>,
++{
++    type Output = <T as LockingDsl<LockInShareMode>>::Output;
++
++    fn lock_in_share_mode(self) -> Self::Output {
++        self.with_lock(LockInShareMode)
++    }
++}
++
++#[derive(Debug, Clone, Copy, QueryId)]
++pub struct LockInShareMode;
++
++impl QueryFragment<Mysql> for LockInShareMode {
++    fn walk_ast<'b>(&'b self, mut out: AstPass<'_, 'b, Mysql>) -> QueryResult<()> {
++        out.push_sql(" LOCK IN SHARE MODE");
++        Ok(())
++    }
++}
++
+ #[allow(dead_code)] // Not really dead, Rust can't see it.
+ #[derive(Debug, Clone)]
+ pub struct OnDuplicateKeyUpdate<T, U, Op, Ret, DB, X>(
+diff --git a/syncstorage-mysql/src/models.rs b/syncstorage-mysql/src/models.rs
+index 1114f21..fb54649 100644
+--- a/syncstorage-mysql/src/models.rs
++++ b/syncstorage-mysql/src/models.rs
+@@ -25,6 +25,7 @@ use syncstorage_settings::{Quota, DEFAULT_MAX_TOTAL_RECORDS};
+
+ use super::{
+     batch,
++    diesel_ext::LockInShareModeDsl,
+     error::DbError,
+     pool::{CollectionCache, Conn},
+     schema::{bso, collections, user_collections},
+@@ -179,7 +180,7 @@ impl MysqlDb {
+             .select(user_collections::modified)
+             .filter(user_collections::user_id.eq(user_id))
+             .filter(user_collections::collection_id.eq(collection_id))
+-            .for_share()
++            .lock_in_share_mode()
+             .first(&mut *self.conn.write()?)
+             .optional()?;
+         if let Some(modified) = modified {