allow shrinking to be in progress during scan_account_storage

runtime/src/accounts_db.rs

@@ -4942,7 +4942,8 @@ impl AccountsDb {
             // If the slot is not in the cache, then all the account information must have
             // been flushed. This is guaranteed because we only remove the rooted slot from
             // the cache *after* we've finished flushing in `flush_slot_cache`.
-            if let Some(storage) = self.storage.get_slot_storage_entry(slot) {
+            // Scanning is occurring in the foreground, so shrinking could be running in the background.
+            if let Some(storage) = self.storage.get_slot_storage_entry_shrinking_in_progress_ok(slot) {
                 storage
                     .accounts
                     .account_iter()