Add TaskRunner wrapper for WorkerPool.

base/threading/worker_pool.h

Index: base/threading/worker_pool.h
diff --git a/base/threading/worker_pool.h b/base/threading/worker_pool.h
index 6694830e7d7a560612bf48b5b6ed279737fa3964..02c5c99944f117eb62e0bd92b6c3b9ed617a762d 100644
--- a/base/threading/worker_pool.h
+++ b/base/threading/worker_pool.h
@@ -8,6 +8,7 @@
 
 #include "base/base_export.h"
 #include "base/callback_forward.h"
+#include "base/memory/ref_counted.h"
 
 class Task;
 
@@ -17,6 +18,8 @@ class Location;
 
 namespace base {
 
+class TaskRunner;
+
 // This is a facility that runs tasks that don't require a specific thread or
 // a message loop.
 //
@@ -41,6 +44,16 @@ class BASE_EXPORT WorkerPool {
                                const Closure& task,
                                const Closure& reply,
                                bool task_is_slow);
+
+  // Return true if the current thread is one that this WorkerPool runs tasks
+  // on.  (Note that if the Windows worker pool is used without going through
+  // this WorkerPool interface, RunsTasksOnCurrentThread would return false on
+  // those threads.)
+  static bool RunsTasksOnCurrentThread();
+
+  // Get a TaskRunner wrapper which posts to the WorkerPool using the given
+  // |task_is_slow| behavior.
+  static scoped_refptr<TaskRunner> GetTaskRunner(bool task_is_slow);

[willchan no longer on Chromium, 2012/04/24 23:41:50]

How about you also store a leaky LazyInstance for a scoped_refptr for the
TaskRunner? I worry that people will do dumb things like TaskRunner* task_runner
= base::WorkerPool::GetTaskRunner(), which will cause the TaskRunner to get
immediately deleted due to the implicit T* operator.

[mattm, 2012/04/25 00:57:35]

Done.  Had to make a holder class to initialize the scoped_refptr

 };
 
 }  // namespace base