title: UnsatisfiedLinkError when unit testing WritableNativeMap
body: <p>I am currently creating an Android library for use in a react native project. I need to emit a map to javascript, so I'm using react native's WriteableMap class. Unfortunately, the class loads the reactnativejni SO in a static block, which leads to an UnsatisfiedLinkError during unit tests. I'm using JUnit and Mockito to test.</p>
  
  <p>My code:</p>
  
  <pre><code>@Override
  public void onSomething() {
      WritableMap params = Arguments.createMap();
  
      //fill map
  
      sendEvent("onChange", params);
  }
  </code></pre>
  
  <p>The error:</p>
  
  <pre><code>java.lang.UnsatisfiedLinkError: no reactnativejni in java.library.path
    at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1857)
    at java.lang.Runtime.loadLibrary0(Runtime.java:870)
    at java.lang.System.loadLibrary(System.java:1119)
    at com.facebook.soloader.SoLoader.loadLibrary(SoLoader.java:172)
    at com.facebook.react.bridge.NativeMap.&lt;clinit&gt;(NativeMap.java:23)
    at com.facebook.react.bridge.Arguments.createMap(Arguments.java:29)
    at me.MyClass.onSomething(myClass.java:23)
  </code></pre>
  
  <p>I started using the <code>Arguments.createMap()</code> method after seeing a comment about stubbing WriteableMap for unit tests, but it's static and I would prefer to not have to stub a static method.</p>
  
  <p>Is there some way to get rid of this error when running unit tests?</p>