Consolidate JNI registrations for mojo system.

mojo/android/system/mojo_jni_registrar.h

Index: mojo/android/system/mojo_jni_registrar.h
diff --git a/mojo/android/system/mojo_jni_registrar.h b/mojo/android/system/mojo_jni_registrar.h
new file mode 100644
index 0000000000000000000000000000000000000000..e4f3ebcae709a892e7d5c23e14bb2c27f496cb98
--- /dev/null
+++ b/mojo/android/system/mojo_jni_registrar.h
@@ -0,0 +1,19 @@
+// Copyright (c) 2017 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.
+
+#ifndef MOJO_ANDROID_SYSTEM_MOJO_JNI_REGISTRAR_H_
+#define MOJO_ANDROID_SYSTEM_MOJO_JNI_REGISTRAR_H_
+
+#include <jni.h>
+
+namespace mojo {
+namespace android {
+
+// Register all JNI bindings necessary for mojo system.
+bool RegisterSystemJni(JNIEnv* env);
+
+}  // namespace android
+}  // namespace mojo
+
+#endif  // MOJO_ANDROID_SYSTEM_MOJO_JNI_REGISTRAR_H_