Update from https://crrev.com/305340

sandbox/linux/tests/test_utils.h

Index: sandbox/linux/tests/test_utils.h
diff --git a/sandbox/linux/tests/test_utils.h b/sandbox/linux/tests/test_utils.h
index 3269847b0e1835ed39f64fea93b14d66ebc180a2..1d9eb791cc68cd76881c2388d3fc4d21e5201aef 100644
--- a/sandbox/linux/tests/test_utils.h
+++ b/sandbox/linux/tests/test_utils.h
@@ -5,6 +5,8 @@
 #ifndef SANDBOX_LINUX_TESTS_TEST_UTILS_H_
 #define SANDBOX_LINUX_TESTS_TEST_UTILS_H_
 
+#include <sys/types.h>
+
 #include "base/basictypes.h"
 
 namespace sandbox {
@@ -13,6 +15,10 @@ namespace sandbox {
 class TestUtils {
  public:
   static bool CurrentProcessHasChildren();
+  // |pid| is the return value of a fork()-like call. This
+  // makes sure that if fork() succeeded the child exits
+  // and the parent waits for it.
+  static void HandlePostForkReturn(pid_t pid);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(TestUtils);