[heap] Make link from optimized code to inlined code explicit.

src/heap/objects-visiting.h

Index: src/heap/objects-visiting.h
diff --git a/src/heap/objects-visiting.h b/src/heap/objects-visiting.h
index f0925a71c7fdeba2dce02d2c8629a4d227529d25..16034d0375bd365bdd727013a1b1db03ad90a976 100644
--- a/src/heap/objects-visiting.h
+++ b/src/heap/objects-visiting.h
@@ -383,10 +383,6 @@ class StaticMarkingVisitor : public StaticVisitorBase {
   // references, possibly treating some entries weak.
   static void MarkOptimizedCodeMap(Heap* heap, FixedArray* code_map);
 
-  // Mark non-optimized code for functions inlined into the given optimized
-  // code. This will prevent it from being flushed.
-  static void MarkInlinedFunctionsCode(Heap* heap, Code* code);
-
   // Code flushing support.
   INLINE(static bool IsFlushable(Heap* heap, JSFunction* function));
   INLINE(static bool IsFlushable(Heap* heap, SharedFunctionInfo* shared_info));