Web MIDI: implement sending for dynamic manager instantiation on Windows

media/midi/dynamically_initialized_midi_manager_win.h

Index: media/midi/dynamically_initialized_midi_manager_win.h
diff --git a/media/midi/dynamically_initialized_midi_manager_win.h b/media/midi/dynamically_initialized_midi_manager_win.h
index ae492eed719dd7d2efdf54f33443153c891fd18d..176ca16bf16f04d1d0d16fe861980ba546b272a5 100644
--- a/media/midi/dynamically_initialized_midi_manager_win.h
+++ b/media/midi/dynamically_initialized_midi_manager_win.h
@@ -16,6 +16,7 @@
 
 namespace base {
 class SingleThreadTaskRunner;
+class TimeDelta;
 }  // namespace base
 
 namespace midi {
@@ -57,6 +58,7 @@ class DynamicallyInitializedMidiManagerWin final
   // Posts a task to TaskRunner, and ensures that the instance keeps alive while
   // the task is running.
   void PostTask(const base::Closure&);
+  void PostDelayedTask(const base::Closure&, base::TimeDelta delay);
 
   // Posts a reply task to the I/O thread that hosts MidiManager instance, runs
   // it safely, and ensures that the instance keeps alive while the task is
@@ -76,6 +78,11 @@ class DynamicallyInitializedMidiManagerWin final
                                std::vector<T>* known_ports,
                                std::vector<T>* active_ports);
 
+  // Sends MIDI data on TaskRunner.
+  void SendOnTaskRunner(MidiManagerClient* client,
+                        uint32_t port_index,
+                        const std::vector<uint8_t>& data);
+
   // Holds an unique instance ID.
   const int instance_id_;