Manage MIDI related objects and sessions' lifecycles correctly

media/midi/midi_manager_usb_unittest.cc

Index: media/midi/midi_manager_usb_unittest.cc
diff --git a/media/midi/midi_manager_usb_unittest.cc b/media/midi/midi_manager_usb_unittest.cc
index b4f939f35aa0a6221f12c3bc171f369ac2cec2d1..1eeae9e0121360ee690f4bf8353a763ee62962ec 100644
--- a/media/midi/midi_manager_usb_unittest.cc
+++ b/media/midi/midi_manager_usb_unittest.cc
@@ -78,7 +78,7 @@ class FakeMidiManagerClient : public MidiManagerClient {
         logger_(logger) {}
   ~FakeMidiManagerClient() override {}
 
-  void CompleteStartSession(int client_id, MidiResult result) override {
+  void CompleteStartSession(MidiResult result) override {
     complete_start_session_ = true;
     result_ = result;
   }
@@ -159,7 +159,7 @@ class MidiManagerUsbTest : public ::testing::Test {
  protected:
   void Initialize() {
     client_.reset(new FakeMidiManagerClient(&logger_));
-    manager_->StartSession(client_.get(), 0);
+    manager_->StartSession(client_.get());
   }
 
   void Finalize() {