sandbox tests: Adapt test expectations to new CHECK() behavior

sandbox/linux/tests/unit_tests.cc

 // Copyright (c) 2012 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 <fcntl.h>
 #include <poll.h>
 #include <signal.h>
 #include <stddef.h>
 #include <stdio.h>
 #include <sys/resource.h>
@@ skipping 270 matching lines @@
 
   bool subprocess_terminated_normally = WIFEXITED(status);
   ASSERT_TRUE(subprocess_terminated_normally) << "Exit status: " << status
                                               << " " << details;
   int subprocess_exit_status = WEXITSTATUS(status);
   ASSERT_EQ(1, subprocess_exit_status) << details;
 
   bool subprocess_exited_without_matching_message =
       msg.find(expected_msg) == std::string::npos;
 
-// In official builds CHECK messages are dropped, so look for SIGABRT or SIGILL.
+// In official builds CHECK messages are dropped, look for SIGABRT or SIGTRAP.
 // See https://crbug.com/437312 and https://crbug.com/612507.
 #if defined(OFFICIAL_BUILD) && defined(NDEBUG) && !defined(OS_ANDROID)
   if (subprocess_exited_without_matching_message) {
-    static const char kSigIllegalMessage[] = "Received signal 4";
+    static const char kSigTrapMessage[] = "Received signal 5";
     static const char kSigAbortMessage[] = "Received signal 6";
     subprocess_exited_without_matching_message =
-        msg.find(kSigIllegalMessage) == std::string::npos &&
+        msg.find(kSigTrapMessage) == std::string::npos &&
         msg.find(kSigAbortMessage) == std::string::npos;
   }
 #endif
   EXPECT_FALSE(subprocess_exited_without_matching_message) << details;
 }
 
 void UnitTests::DeathSEGVMessage(int status,
                                  const std::string& msg,
                                  const void* aux) {
   std::string details(TestFailedMessage(msg));
@@ skipping 46 matching lines @@
   fflush(stderr);
   _exit(kExitWithAssertionFailure);
 }
 
 void UnitTests::IgnoreThisTest() {
   fflush(stderr);
   _exit(kIgnoreThisTest);
 }
 
 }  // namespace