Retain maps embedded in optimized code for several garbage collections.

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 16170 matching lines @@
       "s(o);");
   CHECK(try_catch.HasCaught());
   v8::String::Utf8Value value(try_catch.Exception());
   CHECK_EQ(0, strcmp(*value, "Hey!"));
 }
 
 
 TEST(Regress528) {
   v8::V8::Initialize();
   v8::Isolate* isolate = CcTest::isolate();
+  i::FLAG_retain_maps_for_n_gc = 0;
   v8::HandleScope scope(isolate);
   v8::Local<Context> other_context;
   int gc_count;
 
   // Create a context used to keep the code from aging in the compilation
   // cache.
   other_context = Context::New(isolate);
 
   // Context-dependent context data creates reference from the compilation
   // cache to the global object.
@@ skipping 5382 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);
 }