Make test unthreaded so other tests don't interfere with heap size

test/cctest/test-api.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 6545 matching lines @@
     CcTest::heap()->CollectGarbage(i::NEW_SPACE);
   }
   // A single GC should be enough to reclaim the memory, since we are using
   // phantom handles.
   CHECK_LT(CcTest::heap()->SizeOfObjects(), big_heap_size - 200000);
   CHECK(object_a.flag);
   CHECK(object_b.flag);
 }
 
 
-THREADED_TEST(IndependentWeakHandle) {
+TEST(IndependentWeakHandle) {
   IndependentWeakHandle(false, false);
   IndependentWeakHandle(false, true);
   IndependentWeakHandle(true, false);
   IndependentWeakHandle(true, true);
 }
 
 
 class Trivial {
  public:
   explicit Trivial(int x) : x_(x) {}
@@ skipping 15316 matching lines @@
   }
   {
     v8::TryCatch try_catch;
     uint16_t* data = reinterpret_cast<uint16_t*>(buffer);
     CHECK(v8::String::NewFromTwoByte(isolate, data, v8::String::kNormalString,
                                      length).IsEmpty());
     CHECK(!try_catch.HasCaught());
   }
   free(buffer);
 }