Add REAL_TASK_SCHEDULER option in TestBrowserThreadBundle.

content/public/test/test_browser_thread_bundle.h

Index: content/public/test/test_browser_thread_bundle.h
diff --git a/content/public/test/test_browser_thread_bundle.h b/content/public/test/test_browser_thread_bundle.h
index dbb65f95e00ac6c4439f8ae5ab62b6640eea44e6..859c4798f7803c973492875886c83e7e56074fd3 100644
--- a/content/public/test/test_browser_thread_bundle.h
+++ b/content/public/test/test_browser_thread_bundle.h
@@ -25,6 +25,10 @@
 // FileDescriptorWatcher. Most of the time, IO_MAINLOOP avoids needing to use a
 // REAL_IO_THREAD.
 //
+// If a test needs a TaskScheduler that doesn't run its tasks on the main

[robliao, 2017/01/12 20:15:02]

Nit: s/that doesn't run its tasks on the main thread/runs tasks in a threadpool/

[fdoray, 2017/01/12 21:25:56]

Done. (dedicated thread instead of threadpool because tasks will run in a pool
of 1 thread)

+// thread, it should use REAL_TASK_SCHEDULER. Usage of this option should be
+// justified as it is easier to understand and debug a single-threaded test.

[gab, 2017/01/12 19:50:27]

s/test/unit test/

[fdoray, 2017/01/12 21:25:56]

Done.

+//
 // For some tests it is important to emulate real browser startup. During real
 // browser startup, the main MessageLoop is created before other threads.
 // Passing DONT_START_THREADS to constructor will delay creating other threads
@@ -43,6 +47,7 @@
 namespace base {
 class MessageLoop;
 namespace test {
+class ScopedAsyncTaskScheduler;
 class ScopedTaskScheduler;
 }  // namespace test
 }  // namespace base
@@ -60,8 +65,9 @@ class TestBrowserThreadBundle {
     DEFAULT = 0x00,
     IO_MAINLOOP = 0x01,
     REAL_DB_THREAD = 0x02,
-    REAL_FILE_THREAD = 0x08,
-    REAL_IO_THREAD = 0x10,
+    REAL_FILE_THREAD = 0x04,
+    REAL_IO_THREAD = 0x08,
+    REAL_TASK_SCHEDULER = 0x10,
     DONT_CREATE_THREADS = 0x20,

[gab, 2017/01/12 19:50:27]

Change 0xFF syntax to 

1 << 0
1 << 1
1 << 2
1 << 3
...

easier to parse and make no mistakes.

[robliao, 2017/01/12 20:15:02]

+1

[fdoray, 2017/01/12 21:25:56]

Done.

   };
 
@@ -78,7 +84,9 @@ class TestBrowserThreadBundle {
   void Init();
 
   std::unique_ptr<base::MessageLoop> message_loop_;
-  std::unique_ptr<base::test::ScopedTaskScheduler> task_scheduler_;
+  std::unique_ptr<base::test::ScopedAsyncTaskScheduler>
+      scoped_async_task_scheduler_;
+  std::unique_ptr<base::test::ScopedTaskScheduler> scoped_task_scheduler_;
   std::unique_ptr<TestBrowserThread> ui_thread_;
   std::unique_ptr<TestBrowserThread> db_thread_;
   std::unique_ptr<TestBrowserThread> file_thread_;