title: Surprised error while building apps "Couldn't find outer class" after update to gradle3.1.0-beta1(Android Studio 3.1 Beta1)
body: <p>run: ./gradlew clean assembleDebug</p>
  
  <pre><code>Exception in thread "main" java.lang.NullPointerException: Couldn't find outer class xxxxx/SomeClass$someMethod$1$1$2 of xxxx/SomeClass$someMethod$1$1$2$1
  
  execution failed for task ':app:transformClassesWithDesugarForDevDebug'.
  </code></pre>
  
  <p><a href="https://issuetracker.google.com/issues/72750890" rel="noreferrer">issue</a></p>
  
  <p>Same problem <a href="https://www.reddit.com/r/androiddev/comments/7u8tug/android_studio_31_beta_1_is_available/" rel="noreferrer">https://www.reddit.com/r/androiddev/comments/7u8tug/android_studio_31_beta_1_is_available/</a></p>