title: Firebase 4.3.0 play services resolver error
body: <p>I just installed <code>FirebaseMessaging.unitypackage</code> in Unity in a fresh project. First I updated version handler and got a success message, then I selected <strong>"Play services resolver -> Android resolver -> Resolve"</strong> and I got a following error:</p>
  
  <pre><code>NullReferenceException: Object reference not set to an instance of an object
  GooglePlayServices.ResolverVer1_1.GenerateGradleProperties (System.Collections.Generic.Dictionary`2 properties)
  GooglePlayServices.ResolverVer1_1.GradleResolution (System.String destinationDirectory, System.String androidSdkPath, Boolean logErrorOnMissingArtifacts, System.Action`1 resolutionComplete)
  GooglePlayServices.ResolverVer1_1.DoResolutionUnsafe (Google.JarResolver.PlayServicesSupport svcSupport, System.String destinationDirectory, System.Action resolutionComplete)
  GooglePlayServices.ResolverVer1_1+&lt;DoResolution&gt;c__AnonStorey3.&lt;&gt;m__0 ()
  GooglePlayServices.ResolverVer1_1.UpdateTryResolution ()
  UnityEditor.EditorApplication.Internal_CallUpdateFunctions () (at C:/buildslave/unity/build/Editor/Mono/EditorApplication.cs:127)
  </code></pre>