EDK: Make mojo::platform::TaskRunner's PostTask() take an std::function<void()>.

mojo/edk/platform/task_runner.h

Index: mojo/edk/platform/task_runner.h
diff --git a/mojo/edk/platform/task_runner.h b/mojo/edk/platform/task_runner.h
index e54213f34bd5da7178cbae6b881771d3b09b6348..c9af1ca98f2d4aa118049af9fe50d4bf27ed816d 100644
--- a/mojo/edk/platform/task_runner.h
+++ b/mojo/edk/platform/task_runner.h
@@ -8,6 +8,8 @@
 #ifndef MOJO_EDK_PLATFORM_TASK_RUNNER_H_
 #define MOJO_EDK_PLATFORM_TASK_RUNNER_H_
 
+#include <functional>
+
 #include "base/callback_forward.h"
 #include "mojo/edk/util/ref_counted.h"
 #include "mojo/public/cpp/system/macros.h"
@@ -25,7 +27,8 @@ class TaskRunner : public util::RefCountedThreadSafe<TaskRunner> {
   // Posts a task to this task runner (i.e., schedule the task). The task must
   // be run (insofar as this can be guaranteed). (This must not run the task
   // synchronously.)
-  // TODO(vtl): Replace the |base::Closure| with |std::function<void()>|.
+  // TODO(vtl): Remove the |base::Closure| version.
+  virtual void PostTask(std::function<void()>&& task) = 0;
   virtual void PostTask(const base::Closure& task) = 0;
 
   // Returns true if this task runner may run tasks on the current thread, false