Replace use of deprecated C Standard library headers in C++ code.

Change-Id: I9fa6630c7e4bdb2897df34d417635d8c7d8253bc
Signed-off-by: Tyler Chatow <tchatow@gmail.com>
diff --git a/aos/util/death_test_log_implementation.h b/aos/util/death_test_log_implementation.h
index f061c61..7065141 100644
--- a/aos/util/death_test_log_implementation.h
+++ b/aos/util/death_test_log_implementation.h
@@ -1,7 +1,7 @@
 #ifndef AOS_UTIL_DEATH_TEST_LOG_IMPLEMENTATION_H_
 #define AOS_UTIL_DEATH_TEST_LOG_IMPLEMENTATION_H_
 
-#include <stdlib.h>
+#include <cstdlib>
 
 #include "aos/logging/implementations.h"
 
@@ -11,7 +11,8 @@
 // Prints all FATAL messages to stderr and then abort(3)s before the regular
 // stuff can print out anything else. Ignores all other messages.
 // This is useful in death tests that expect a LOG(FATAL) to cause the death.
-class DeathTestLogImplementation : public logging::HandleMessageLogImplementation {
+class DeathTestLogImplementation
+    : public logging::HandleMessageLogImplementation {
  public:
   virtual void HandleMessage(const logging::LogMessage &message) override {
     if (message.level == FATAL) {