Copy fbjni library from react-native

lib/fb/jni/java/UnknownCppException.java

@@ -0,0 +1,25 @@
+/*
+ * 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.
+ */
+
+package com.facebook.jni;
+
+import com.facebook.proguard.annotations.DoNotStrip;
+
+@DoNotStrip
+public class UnknownCppException extends CppException {
+  @DoNotStrip
+  public UnknownCppException() {
+    super("Unknown");
+  }
+
+  @DoNotStrip
+  public UnknownCppException(String message) {
+    super(message);
+  }
+}