Add serializer test case to bug fix in r24871.

test/cctest/test-serialize.cc

 // Copyright 2007-2010 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 808 matching lines @@
 
   int result_int;
   CHECK(copy_result->ToInt32(&result_int));
   CHECK_EQ(7, result_int);
 
   delete cache;
   source.Dispose();
 }
 
 
-TEST(SerializeToplevelLargeString) {
+TEST(SerializeToplevelLargeStrings) {
   FLAG_serialize_toplevel = true;
   LocalContext context;
   Isolate* isolate = CcTest::i_isolate();
+  Factory* f = isolate->factory();
   isolate->compilation_cache()->Disable();  // Disable same-isolate code cache.
 
   v8::HandleScope scope(CcTest::isolate());
 
-  Vector<const uint8_t> source = ConstructSource(
+  Vector<const uint8_t> source_s = ConstructSource(
       STATIC_CHAR_VECTOR("var s = \""), STATIC_CHAR_VECTOR("abcdef"),
-      STATIC_CHAR_VECTOR("\"; s"), 1000000);
+      STATIC_CHAR_VECTOR("\";"), 1000000);
+  Vector<const uint8_t> source_t = ConstructSource(
+      STATIC_CHAR_VECTOR("var t = \""), STATIC_CHAR_VECTOR("uvwxyz"),
+      STATIC_CHAR_VECTOR("\"; s + t"), 999999);
   Handle<String> source_str =
-      isolate->factory()->NewStringFromOneByte(source).ToHandleChecked();
+      f->NewConsString(f->NewStringFromOneByte(source_s).ToHandleChecked(),
+                       f->NewStringFromOneByte(source_t).ToHandleChecked())
+          .ToHandleChecked();
 
   Handle<JSObject> global(isolate->context()->global_object());
   ScriptData* cache = NULL;
 
   Handle<SharedFunctionInfo> orig = Compiler::CompileScript(
       source_str, Handle<String>(), 0, 0, false,
       Handle<Context>(isolate->native_context()), NULL, &cache,
       v8::ScriptCompiler::kProduceCodeCache, NOT_NATIVES_CODE);
 
   Handle<SharedFunctionInfo> copy;
   {
     DisallowCompilation no_compile_expected(isolate);
     copy = Compiler::CompileScript(
         source_str, Handle<String>(), 0, 0, false,
         Handle<Context>(isolate->native_context()), NULL, &cache,
         v8::ScriptCompiler::kConsumeCodeCache, NOT_NATIVES_CODE);
   }
   CHECK_NE(*orig, *copy);
 
   Handle<JSFunction> copy_fun =
       isolate->factory()->NewFunctionFromSharedFunctionInfo(
           copy, isolate->native_context());
 
   Handle<Object> copy_result =
       Execution::Call(isolate, copy_fun, global, 0, NULL).ToHandleChecked();
 
-  CHECK_EQ(6 * 1000000, Handle<String>::cast(copy_result)->length());
-  CHECK(isolate->heap()->InSpace(HeapObject::cast(*copy_result), LO_SPACE));
+  CHECK_EQ(6 * 1999999, Handle<String>::cast(copy_result)->length());
+  Handle<Object> property = JSObject::GetDataProperty(
+      isolate->global_object(), f->NewStringFromAsciiChecked("s"));
+  CHECK(isolate->heap()->InSpace(HeapObject::cast(*property), LO_SPACE));
+  property = JSObject::GetDataProperty(isolate->global_object(),
+                                       f->NewStringFromAsciiChecked("t"));
+  CHECK(isolate->heap()->InSpace(HeapObject::cast(*property), LO_SPACE));
   // Make sure we do not serialize too much, e.g. include the source string.
-  CHECK_LT(cache->length(), 7000000);
+  CHECK_LT(cache->length(), 13000000);
 
   delete cache;
-  source.Dispose();
+  source_s.Dispose();
+  source_t.Dispose();
 }
 
 
 TEST(SerializeToplevelThreeBigStrings) {
   FLAG_serialize_toplevel = true;
   LocalContext context;
   Isolate* isolate = CcTest::i_isolate();
   Factory* f = isolate->factory();
   isolate->compilation_cache()->Disable();  // Disable same-isolate code cache.
 
@@ skipping 398 matching lines @@
     {
       DisallowCompilation no_compile(reinterpret_cast<Isolate*>(isolate2));
       script = v8::ScriptCompiler::CompileUnbound(
           isolate2, &source, v8::ScriptCompiler::kConsumeCodeCache);
     }
     v8::Local<v8::Value> result = script->BindToCurrentContext()->Run();
     CHECK(result->ToString()->Equals(v8_str("XY")));
   }
   isolate2->Dispose();
 }