Workaround native module dependency in Jest environment

Reviewed By: josephsavona

Differential Revision: D4225750

fbshipit-source-id: 6ac5a5cc1869232861977ea214970804acd7e39d

Libraries/Utilities/Platform.android.js

@@ -15,7 +15,8 @@
 var Platform = {
   OS: 'android',
   get Version() {
-    return require('NativeModules').AndroidConstants.Version;
+    const AndroidConstants = require('NativeModules').AndroidConstants;
+    return AndroidConstants && AndroidConstants.Version;
   },
   select: (obj: Object) => obj.android,
 };