[heap] Concurrently free empty typed slot set chunks.

src/heap/mark-compact.cc

Index: src/heap/mark-compact.cc
diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
index 08472e5b10448949ef761f91de3fbdaedeead34b..aae6593cc5ab0c47e3a2eb24bcb45b1aac0b2052 100644
--- a/src/heap/mark-compact.cc
+++ b/src/heap/mark-compact.cc
@@ -3865,6 +3865,12 @@ int MarkCompactCollector::Sweeper::ParallelSweepPage(Page* page,
     } else {
       max_freed = RawSweep(page, REBUILD_FREE_LIST, free_space_mode);
     }
+
+    // After finishing sweeping of a page we clean up its remembered set.
+    if (page->typed_old_to_new_slots()) {
+      page->typed_old_to_new_slots()->FreeToBeFreedChunks();
+    }
+
     {
       base::LockGuard<base::Mutex> guard(&mutex_);
       swept_list_[identity].Add(page);