Run ScopedTaskScheduler tasks synchronously.

content/public/test/test_browser_thread_bundle.cc

Index: content/public/test/test_browser_thread_bundle.cc
diff --git a/content/public/test/test_browser_thread_bundle.cc b/content/public/test/test_browser_thread_bundle.cc
index d68311235a368c3b0b9b5b24e0f3396b51fc8c98..211ecdfa4ab099dc04ba6b1c6f5f2ce8704b6ab9 100644
--- a/content/public/test/test_browser_thread_bundle.cc
+++ b/content/public/test/test_browser_thread_bundle.cc
@@ -7,6 +7,7 @@
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
+#include "base/test/scoped_task_scheduler.h"
 #include "content/browser/browser_thread_impl.h"
 #include "content/public/test/test_browser_thread.h"
 
@@ -52,6 +53,8 @@ TestBrowserThreadBundle::~TestBrowserThreadBundle() {
   ui_thread_->Stop();
   base::RunLoop().RunUntilIdle();
 
+  task_scheduler_.reset();
+
   // |message_loop_| needs to explicitly go away before fake threads in order
   // for DestructionObservers hooked to |message_loop_| to be able to invoke
   // BrowserThread::CurrentlyOn() -- ref. ~TestBrowserThread().
@@ -71,6 +74,9 @@ void TestBrowserThreadBundle::Init() {
     message_loop_.reset(new base::MessageLoopForUI());
   }
 
+  task_scheduler_.reset(
+      new base::test::ScopedTaskScheduler(message_loop_.get()));
+
   ui_thread_.reset(
       new TestBrowserThread(BrowserThread::UI, message_loop_.get()));