Implement aging of maps embedded in optimized code.

src/heap/mark-compact.h

Index: src/heap/mark-compact.h
diff --git a/src/heap/mark-compact.h b/src/heap/mark-compact.h
index cd2c9b68c834be428cc7475823995e7ec420e7ba..cd289b1a63d0d5aea1e71eb542cf2f3859a11f66 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -616,6 +616,8 @@ class MarkCompactCollector {
 
   bool abort_incremental_marking() const { return abort_incremental_marking_; }
 
+  bool reduce_memory_footprint() const { return reduce_memory_footprint_; }
+
   bool is_compacting() const { return compacting_; }
 
   MarkingParity marking_parity() { return marking_parity_; }