Fix clearing of dead dependent codes and verify weak embedded maps on full GC.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 975fdf8d85a46b98a7d3715c09b798444efaec83..bddcf554bc5bc3d6dcd2bea2fddc9cc62a671479 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -4545,6 +4545,10 @@ class Code: public HeapObject {
 
   void PrintDeoptLocation(int bailout_id);
 
+#ifdef VERIFY_HEAP
+  void VerifyEmbeddedMapsDependency();
+#endif
+
   // Max loop nesting marker used to postpose OSR. We don't take loop
   // nesting that is deeper than 5 levels into account.
   static const int kMaxLoopNestingMarker = 6;
@@ -4691,6 +4695,7 @@ class DependentCodes: public FixedArray {
   static Handle<DependentCodes> Append(Handle<DependentCodes> codes,
                                        Handle<Code> value);
   static inline DependentCodes* cast(Object* object);
+  bool Contains(Code* code);
  private:
   static const int kNumberOfCodesIndex = 0;
   static const int kCodesIndex = 1;