Copy fbjni library from react-native

lib/fb/jni/OnLoad.cpp

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#include <jni/Countable.h>
+#include <fb/Environment.h>
+#include <fb/fbjni.h>
+#include <fb/fbjni/NativeRunnable.h>
+
+using namespace facebook::jni;
+
+void initialize_fbjni() {
+  CountableOnLoad(Environment::current());
+  HybridDataOnLoad();
+  JNativeRunnable::OnLoad();
+  ThreadScope::OnLoad();
+}