Ensure tests check the return of SpawnChild() when they may wait without timeouts

content/common/sandbox_mac_unittest_helper.mm

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/sandbox_mac_unittest_helper.h"
 
 extern "C" {
 #include <sandbox.h>
 }
 
@@ skipping 63 matching lines @@
                                       const char* test_data) {
   std::stringstream s;
   s << static_cast<int>(static_cast<int>(sandbox_type));
   setenv(kSandboxTypeKey, s.str().c_str(), 1);
   setenv(kSandboxTestNameKey, test_name, 1);
   if (test_data)
     setenv(kTestDataKey, test_data, 1);
 
   base::ProcessHandle child_process = SpawnChild("mac_sandbox_test_runner",
                                                  false);
+  if (child_process == base::kNullProcessHandle) {
+    LOG(WARNING) << "SpawnChild failed";
+    return false;
+  }
   int code = -1;
   if (!base::WaitForExitCode(child_process, &code)) {
     LOG(WARNING) << "base::WaitForExitCode failed";
     return false;
   }
   return code == 0;
 }
 
 bool MacSandboxTestCase::BeforeSandboxInit() {
   return true;
@@ skipping 67 matching lines @@
 
   if (!test_case->SandboxedTest()) {
     LOG(ERROR) << sandbox_test_name << "Failed sandboxed test";
     return -1;
   }
 
   return 0;
 }
 
 }  // namespace