Make syzyasan_rtl compile in 64 bit

syzygy/agent/asan/unittest_util.h

Index: syzygy/agent/asan/unittest_util.h
diff --git a/syzygy/agent/asan/unittest_util.h b/syzygy/agent/asan/unittest_util.h
index f1181e60c4e550119e33f16ef6d514f65458d345..43487245618651c97752fef814c84be30d10aaf6 100644
--- a/syzygy/agent/asan/unittest_util.h
+++ b/syzygy/agent/asan/unittest_util.h
@@ -132,6 +132,9 @@ class TestWithAsanLogger : public OnExceptionCallbackTest {
   // Value of the logger instance environment variable before SetUp.
   std::string old_logger_env_;
 
+  // Value of the asan options environment variable before SetUp.
+  std::string old_asan_options_env_;
+
   // Redirection files for the logger.
   base::ScopedFILE logger_stdin_file_;
   base::ScopedFILE logger_stdout_file_;