[heap] Do not invoke GC to make heap iterable.

test/cctest/test-log.cc

 // Copyright 2006-2009 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 467 matching lines @@
     ScopedLoggerInitializer initialize_logger(saved_log, saved_prof, isolate);
     Logger* logger = initialize_logger.logger();
 
     // Compile and run a function that creates other functions.
     CompileRun(
         "(function f(obj) {\n"
         "  obj.test =\n"
         "    (function a(j) { return function b() { return j; } })(100);\n"
         "})(this);");
     logger->StopProfiler();
-    reinterpret_cast<i::Isolate*>(isolate)->heap()->CollectAllGarbage(
-        i::Heap::kMakeHeapIterableMask);
     logger->StringEvent("test-logging-done", "");
 
     // Iterate heap to find compiled functions, will write to log.
     logger->LogCompiledFunctions();
     logger->StringEvent("test-traversal-done", "");
 
     bool exists = false;
     i::Vector<const char> log(
         i::ReadFile(initialize_logger.StopLoggingGetTempFile(), &exists, true));
     CHECK(exists);
@@ skipping 108 matching lines @@
         "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaac"
         "(){})();";
 
     CompileRun(source_text);
 
     // Must not crash.
     logger->LogCompiledFunctions();
   }
   isolate->Dispose();
 }