Do not mark dependent_code arrays as weak in heap snapshot.

test/cctest/test-heap-profiler.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2806 matching lines @@
   const v8::HeapGraphNode* map =
       GetProperty(obj, v8::HeapGraphEdge::kInternal, "map");
   CHECK(map);
   const v8::HeapGraphNode* dependent_code =
       GetProperty(map, v8::HeapGraphEdge::kInternal, "dependent_code");
   if (!dependent_code) return;
   int count = dependent_code->GetChildrenCount();
   CHECK_NE(0, count);
   for (int i = 0; i < count; ++i) {
     const v8::HeapGraphEdge* prop = dependent_code->GetChild(i);
-    CHECK_EQ(v8::HeapGraphEdge::kWeak, prop->GetType());
+    CHECK_EQ(v8::HeapGraphEdge::kInternal, prop->GetType());
   }
 }
 
 
 static inline i::Address ToAddress(int n) {
   return reinterpret_cast<i::Address>(n);
 }
 
 
 TEST(AddressToTraceMap) {
@@ skipping 247 matching lines @@
       "      a[i] = i;\n"
       "  for (var i = 0; i < 3; ++i)\n"
       "      a.shift();\n"
       "}\n");
 
   CcTest::heap()->CollectGarbage(v8::internal::NEW_SPACE);
   // Should not crash.
 
   heap_profiler->StopSamplingHeapProfiler();
 }