Flush SequenceWorkerPool tasks after each unit test.

base/threading/sequenced_worker_pool_unittest.cc

Index: base/threading/sequenced_worker_pool_unittest.cc
===================================================================
--- base/threading/sequenced_worker_pool_unittest.cc	(revision 176718)
+++ base/threading/sequenced_worker_pool_unittest.cc	(working copy)
@@ -701,8 +701,8 @@
   }
 
   void StopTaskRunner() {
-    // Make sure all tasks (including delayed ones) are run before shutting
-    // down.
+    // Make sure all tasks are run before shutting down. Delayed tasks are
+    // not run, they're simply deleted.
     pool_owner_->pool()->FlushForTesting();
     pool_owner_->pool()->Shutdown();
     // Don't reset |pool_owner_| here, as the test may still hold a
@@ -741,8 +741,8 @@
   }
 
   void StopTaskRunner() {
-    // Make sure all tasks (including delayed ones) are run before shutting
-    // down.
+    // Make sure all tasks are run before shutting down. Delayed tasks are
+    // not run, they're simply deleted.
     pool_owner_->pool()->FlushForTesting();
     pool_owner_->pool()->Shutdown();
     // Don't reset |pool_owner_| here, as the test may still hold a
@@ -782,8 +782,8 @@
   }
 
   void StopTaskRunner() {
-    // Make sure all tasks (including delayed ones) are run before shutting
-    // down.
+    // Make sure all tasks are run before shutting down. Delayed tasks are
+    // not run, they're simply deleted.
     pool_owner_->pool()->FlushForTesting();
     pool_owner_->pool()->Shutdown();
     // Don't reset |pool_owner_| here, as the test may still hold a