Web MIDI: introduce MidiManager::Shutdown to shutdown gracefully

media/midi/midi_manager_mac_unittest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/midi/midi_manager_mac.h"
 
 #include <CoreMIDI/MIDIServices.h>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 87 matching lines @@
   bool unexpected_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeMidiManagerClient);
 };
 
 class MidiManagerMacTest : public ::testing::Test {
  public:
   MidiManagerMacTest()
       : manager_(new MidiManagerMac),
         message_loop_(new base::MessageLoop) {}
+  ~MidiManagerMacTest() override {
+    manager_->Shutdown();
+    base::RunLoop run_loop;
+    run_loop.RunUntilIdle();
+  }
 
  protected:
   void StartSession(MidiManagerClient* client) {
     manager_->StartSession(client);
   }
   void EndSession(MidiManagerClient* client) {
     manager_->EndSession(client);
   }
 
  private:
@@ skipping 35 matching lines @@
   if (ep)
     MIDIEndpointDispose(ep);
   if (midi_client)
     MIDIClientDispose(midi_client);
 }
 
 }  // namespace
 
 }  // namespace midi
 }  // namespace media