Update from https://crrev.com/316786

sandbox/linux/services/thread_helpers_unittests.cc

Index: sandbox/linux/services/thread_helpers_unittests.cc
diff --git a/sandbox/linux/services/thread_helpers_unittests.cc b/sandbox/linux/services/thread_helpers_unittests.cc
index a36fd2975f81da18dc32f53ae221da9475f65483..7f99aaf2a16898ad198b33633974bcfde5d8a6e0 100644
--- a/sandbox/linux/services/thread_helpers_unittests.cc
+++ b/sandbox/linux/services/thread_helpers_unittests.cc
@@ -27,6 +27,9 @@ namespace sandbox {
 
 namespace {
 
+// These tests fail under ThreadSanitizer, see http://crbug.com/342305
+#if !defined(THREAD_SANITIZER)
+
 int GetRaceTestIterations() {
   if (IsRunningOnValgrind()) {
     return 2;
@@ -51,31 +54,29 @@ class ScopedProcSelfTask {
   DISALLOW_COPY_AND_ASSIGN(ScopedProcSelfTask);
 };
 
-#if defined(THREAD_SANITIZER)
-// These tests fail under ThreadSanitizer, see http://crbug.com/342305
-#define MAYBE_IsSingleThreadedBasic DISABLED_IsSingleThreadedBasic
-#define MAYBE_IsSingleThreadedIterated DISABLED_IsSingleThreadedIterated
-#define MAYBE_IsSingleThreadedStartAndStop DISABLED_IsSingleThreadedStartAndStop
-#else
-#define MAYBE_IsSingleThreadedBasic IsSingleThreadedBasic
-#define MAYBE_IsSingleThreadedIterated IsSingleThreadedIterated
-#define MAYBE_IsSingleThreadedStartAndStop IsSingleThreadedStartAndStop
-#endif
-
-TEST(ThreadHelpers, MAYBE_IsSingleThreadedBasic) {
+TEST(ThreadHelpers, IsSingleThreadedBasic) {
   ScopedProcSelfTask task;
   ASSERT_TRUE(ThreadHelpers::IsSingleThreaded(task.fd()));
-  ASSERT_TRUE(ThreadHelpers::IsSingleThreaded(-1));
+  ASSERT_TRUE(ThreadHelpers::IsSingleThreaded());
 
   base::Thread thread("sandbox_tests");
   ASSERT_TRUE(thread.Start());
   ASSERT_FALSE(ThreadHelpers::IsSingleThreaded(task.fd()));
-  ASSERT_FALSE(ThreadHelpers::IsSingleThreaded(-1));
+  ASSERT_FALSE(ThreadHelpers::IsSingleThreaded());
   // Explicitly stop the thread here to not pollute the next test.
   ASSERT_TRUE(ThreadHelpers::StopThreadAndWatchProcFS(task.fd(), &thread));
 }
 
-TEST(ThreadHelpers, MAYBE_IsSingleThreadedIterated) {
+SANDBOX_TEST(ThreadHelpers, AssertSingleThreaded) {
+  ScopedProcSelfTask task;
+  SANDBOX_ASSERT(ThreadHelpers::IsSingleThreaded(task.fd()));
+  SANDBOX_ASSERT(ThreadHelpers::IsSingleThreaded());
+
+  ThreadHelpers::AssertSingleThreaded(task.fd());
+  ThreadHelpers::AssertSingleThreaded();
+}
+
+TEST(ThreadHelpers, IsSingleThreadedIterated) {
   ScopedProcSelfTask task;
   ASSERT_TRUE(ThreadHelpers::IsSingleThreaded(task.fd()));
 
@@ -89,7 +90,7 @@ TEST(ThreadHelpers, MAYBE_IsSingleThreadedIterated) {
   }
 }
 
-TEST(ThreadHelpers, MAYBE_IsSingleThreadedStartAndStop) {
+TEST(ThreadHelpers, IsSingleThreadedStartAndStop) {
   ScopedProcSelfTask task;
   ASSERT_TRUE(ThreadHelpers::IsSingleThreaded(task.fd()));
 
@@ -106,6 +107,42 @@ TEST(ThreadHelpers, MAYBE_IsSingleThreadedStartAndStop) {
   }
 }
 
+SANDBOX_TEST(ThreadHelpers, AssertSingleThreadedAfterThreadStopped) {
+  SANDBOX_ASSERT(ThreadHelpers::IsSingleThreaded());
+
+  base::Thread thread1("sandbox_tests");
+  base::Thread thread2("sandbox_tests");
+
+  for (int i = 0; i < GetRaceTestIterations(); ++i) {
+    SANDBOX_ASSERT(thread1.Start());
+    SANDBOX_ASSERT(thread2.Start());
+    SANDBOX_ASSERT(!ThreadHelpers::IsSingleThreaded());
+
+    thread1.Stop();
+    thread2.Stop();
+    // This will wait on /proc/ to reflect the state of threads in the
+    // process.
+    ThreadHelpers::AssertSingleThreaded();
+    SANDBOX_ASSERT(ThreadHelpers::IsSingleThreaded());
+  }
+}
+
+// Only run this test in Debug mode, where AssertSingleThreaded() will return
+// in less than 64ms.
+#if !defined(NDEBUG)
+SANDBOX_DEATH_TEST(
+    ThreadHelpers,
+    AssertSingleThreadedDies,
+    DEATH_MESSAGE(
+        ThreadHelpers::GetAssertSingleThreadedErrorMessageForTests())) {
+  base::Thread thread1("sandbox_tests");
+  SANDBOX_ASSERT(thread1.Start());
+  ThreadHelpers::AssertSingleThreaded();
+}
+#endif  // !defined(NDEBUG)
+
+#endif  // !defined(THREAD_SANITIZER)
+
 }  // namespace
 
 }  // namespace sandbox