Use WeakCells in the optimized code map rather than traversing in pause.

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 1b7cef59e47177035be58457cb088c77ba63dbeb..680bab3d7dc3d462cca9a1b903994b57018e0856 100644
--- a/src/heap/mark-compact.h
+++ b/src/heap/mark-compact.h
@@ -671,11 +671,6 @@ class MarkCompactCollector {
   void ProcessAndClearTransitionArrays();
   void AbortTransitionArrays();
 
-  // After all reachable objects have been marked, those entries within
-  // optimized code maps that became unreachable are removed, potentially
-  // trimming or clearing out the entire optimized code map.
-  void ProcessAndClearOptimizedCodeMaps();
-
   // Process non-live references in maps and optimized code.
   void ProcessWeakReferences();