Add missing using statements for JNI types.

media/midi/midi_device_android.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_device_android.h"
 
 #include <string>
 
 #include "jni/MidiDeviceAndroid_jni.h"
 #include "media/midi/midi_output_port_android.h"
 
+using base::android::ScopedJavaLocalRef;
+
 namespace media {
 namespace midi {
 
 MidiDeviceAndroid::MidiDeviceAndroid(JNIEnv* env,
                                      jobject raw_device,
                                      MidiInputPortAndroid::Delegate* delegate)
     : raw_device_(env, raw_device) {
   ScopedJavaLocalRef<jobjectArray> raw_input_ports =
       Java_MidiDeviceAndroid_getInputPorts(env, raw_device);
   jsize num_input_ports = env->GetArrayLength(raw_input_ports.obj());
@@ skipping 33 matching lines @@
 std::string MidiDeviceAndroid::GetDeviceVersion() {
   JNIEnv* env = base::android::AttachCurrentThread();
   ScopedJavaLocalRef<jstring> ret =
       Java_MidiDeviceAndroid_getVersion(env, raw_device_.obj());
   return std::string(env->GetStringUTFChars(ret.obj(), nullptr),
                      env->GetStringUTFLength(ret.obj()));
 }
 
 }  // namespace midi
 }  // namespace media