Add functions to expand PostDelayedTask interface.

base/task_runner.h

Index: base/task_runner.h
diff --git a/base/task_runner.h b/base/task_runner.h
index 752703104931c9b418a3ae56f9905271c55df379..894eb878f603d5fa5fe7030704374b5899533221 100644
--- a/base/task_runner.h
+++ b/base/task_runner.h
@@ -10,6 +10,7 @@
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
 #include "base/memory/ref_counted.h"
+#include "base/time.h"
 
 namespace tracked_objects {
 class Location;
@@ -72,10 +73,13 @@ class BASE_EXPORT TaskRunner
   // It is valid for an implementation to ignore |delay_ms|; that is,
   // to have PostDelayedTask behave the same as PostTask.
   //
-  // TODO(akalin): Make PostDelayedTask use TimeDelta instead.
+  // TODO(tedv): Make PostDelayedTask use TimeDelta instead.
   virtual bool PostDelayedTask(const tracked_objects::Location& from_here,
                                const Closure& task,
                                int64 delay_ms) = 0;
+  virtual bool PostDelayedTask(const tracked_objects::Location& from_here,
+                               const Closure& task,
+                               base::TimeDelta delay) = 0;
 
   // Returns true if the current thread is a thread on which a task
   // may be run, and false if no task will be run on the current