Migrate files to embedder.

samples/android_sample/jni/android_extension.h

Index: samples/android_sample/jni/android_extension.h
diff --git a/samples/android_sample/jni/android_extension.h b/samples/android_sample/jni/android_extension.h
deleted file mode 100644
index 2c24fe77c9b0f1859b3f6f284372e608df320e8f..0000000000000000000000000000000000000000
--- a/samples/android_sample/jni/android_extension.h
+++ /dev/null
@@ -1,15 +0,0 @@
-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-#ifndef ANDROID_EXTENSION_H
-#define ANDROID_EXTENSION_H
-
-#include "include/dart_api.h"
-
-Dart_NativeFunction ResolveName(Dart_Handle name, int argc);
-
-void PlayBackground(const char* path);
-void StopBackground();
-
-#endif