Reland: Preprocess structured stack trace on GC to get rid of code reference.

test/cctest/test-heap.cc

 // Copyright 2012 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 5361 matching lines @@
 TEST(WeakFixedArray) {
   CcTest::InitializeVM();
   v8::HandleScope scope(CcTest::isolate());
 
   Handle<HeapNumber> number = CcTest::i_isolate()->factory()->NewHeapNumber(1);
   Handle<WeakFixedArray> array = WeakFixedArray::Add(Handle<Object>(), number);
   array->Remove(number);
   array->Compact();
   WeakFixedArray::Add(array, number);
 }
+
+
+TEST(PreprocessStackTrace) {
+  // Do not automatically trigger early GC.
+  FLAG_gc_interval = -1;
+  CcTest::InitializeVM();
+  v8::HandleScope scope(CcTest::isolate());
+  v8::TryCatch try_catch;
+  CompileRun("throw new Error();");
+  CHECK(try_catch.HasCaught());
+  Isolate* isolate = CcTest::i_isolate();
+  Handle<Object> exception = v8::Utils::OpenHandle(*try_catch.Exception());
+  Handle<Name> key = isolate->factory()->stack_trace_symbol();
+  Handle<Object> stack_trace =
+      JSObject::GetProperty(exception, key).ToHandleChecked();
+  Handle<Object> code =
+      Object::GetElement(isolate, stack_trace, 3).ToHandleChecked();
+  CHECK(code->IsCode());
+
+  isolate->heap()->CollectAllAvailableGarbage("stack trace preprocessing");
+
+  Handle<Object> pos =
+      Object::GetElement(isolate, stack_trace, 3).ToHandleChecked();
+  CHECK(pos->IsSmi());
+
+  Handle<JSArray> stack_trace_array = Handle<JSArray>::cast(stack_trace);
+  int array_length = Smi::cast(stack_trace_array->length())->value();
+  for (int i = 0; i < array_length; i++) {
+    Handle<Object> element =
+        Object::GetElement(isolate, stack_trace, i).ToHandleChecked();
+    CHECK(!element->IsCode());
+  }
+}