db/batchlog_manager: make structs stats public

Need to rename stats() -> get_stats() because it shadows the now
exported type name.

db/batchlog_manager.hh

@@ -55,6 +55,11 @@ class batchlog_manager : public peering_sharded_service<batchlog_manager> {
 public:
     using post_replay_cleanup = bool_class<class post_replay_cleanup_tag>;
 
+    struct stats {
+        uint64_t write_attempts = 0;
+    };
+
+
 private:
     static constexpr std::chrono::seconds replay_interval = std::chrono::seconds(60);
     static constexpr uint32_t page_size = 128; // same as HHOM, for now, w/out using any heuristics. TODO: set based on avg batch size.
@@ -62,9 +67,7 @@ private:
 
     using clock_type = lowres_clock;
 
-    struct stats {
-        uint64_t write_attempts = 0;
-    } _stats;
+    stats _stats;
 
     seastar::metrics::metric_groups _metrics;
 
@@ -109,7 +112,7 @@ public:
         return _last_replay;
     }
 
-    const stats& stats() const {
+    const stats& get_stats() const {
         return _stats;
     }
 private:

test/boost/batchlog_manager_test.cc

@@ -693,7 +693,7 @@ SEASTAR_TEST_CASE(test_batchlog_replay_write_time) {
 
         auto get_write_attempts = [&] () -> uint64_t {
             return env.batchlog_manager().map_reduce0([] (const db::batchlog_manager& bm) {
-                return bm.stats().write_attempts;
+                return bm.get_stats().write_attempts;
             }, uint64_t(0), std::plus<uint64_t>{}).get();
         };