Do not report unessential weak references 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 1710 matching lines @@
 
   CHECK(!HasWeakGlobalHandle());
 
   v8::Persistent<v8::Object> handle(env->GetIsolate(), v8::Object::New());
   handle.MakeWeak<v8::Value, void>(NULL, PersistentHandleCallback);
 
   CHECK(HasWeakGlobalHandle());
 }
 
 
-TEST(WeakNativeContextRefs) {
-  LocalContext env;
-  v8::HandleScope scope(env->GetIsolate());
-  v8::HeapProfiler* heap_profiler = env->GetIsolate()->GetHeapProfiler();
-
-  const v8::HeapSnapshot* snapshot =
-      heap_profiler->TakeHeapSnapshot(v8_str("weaks"));
-  CHECK(ValidateSnapshot(snapshot));
-  const v8::HeapGraphNode* gc_roots = GetNode(
-      snapshot->GetRoot(), v8::HeapGraphNode::kSynthetic, "(GC roots)");
-  CHECK_NE(NULL, gc_roots);
-  const v8::HeapGraphNode* global_handles = GetNode(
-      gc_roots, v8::HeapGraphNode::kSynthetic, "(Global handles)");
-  CHECK_NE(NULL, global_handles);
-  const v8::HeapGraphNode* native_context = GetNode(
-      global_handles, v8::HeapGraphNode::kHidden, "system / NativeContext");
-  CHECK_NE(NULL, native_context);
-  CHECK(HasWeakEdge(native_context));
-}
-
-
 TEST(SfiAndJsFunctionWeakRefs) {
   LocalContext env;
   v8::HandleScope scope(env->GetIsolate());
   v8::HeapProfiler* heap_profiler = env->GetIsolate()->GetHeapProfiler();
 
   CompileRun(
       "fun = (function (x) { return function () { return x + 1; } })(1);");
   const v8::HeapSnapshot* snapshot =
       heap_profiler->TakeHeapSnapshot(v8_str("fun"));
   CHECK(ValidateSnapshot(snapshot));
   const v8::HeapGraphNode* global = GetGlobalObject(snapshot);
   CHECK_NE(NULL, global);
   const v8::HeapGraphNode* fun =
       GetProperty(global, v8::HeapGraphEdge::kProperty, "fun");
-  CHECK(HasWeakEdge(fun));
+  CHECK(!HasWeakEdge(fun));
   const v8::HeapGraphNode* shared =
       GetProperty(fun, v8::HeapGraphEdge::kInternal, "shared");
-  CHECK(HasWeakEdge(shared));
+  CHECK(!HasWeakEdge(shared));
 }
 
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
 TEST(NoDebugObjectInSnapshot) {
   LocalContext env;
   v8::HandleScope scope(env->GetIsolate());
   v8::HeapProfiler* heap_profiler = env->GetIsolate()->GetHeapProfiler();
 
   v8::internal::Isolate::Current()->debug()->Load();
@@ skipping 194 matching lines @@
       heap_profiler->TakeHeapSnapshot(v8_str("snapshot"));
   CHECK(ValidateSnapshot(snapshot));
   const v8::HeapGraphNode* global = GetGlobalObject(snapshot);
   const v8::HeapGraphNode* foo_func =
       GetProperty(global, v8::HeapGraphEdge::kProperty, "foo");
   CHECK_NE(NULL, foo_func);
   const v8::HeapGraphNode* code =
       GetProperty(foo_func, v8::HeapGraphEdge::kInternal, "code");
   CHECK_NE(NULL, code);
 }