title: Proguard errors when exporting Android project after updating to ADT 20
body: <p>After updating to ADT 20 I can no longer successfully export any of my Android projects. I get:</p>
  
  <pre><code>Proguard returned with error code 1. See console
  </code></pre>
  
  <p>In the console I get tons of the <code>can't find referenced class</code> warnings and occasionally the <code>can't find superclass or interface</code> warning. At the end of the warnings I get something like this:</p>
  
  <pre><code>    You should check if you need to specify additional program jars.
  Warning: there were 199 unresolved references to classes or interfaces.
      You may need to specify additional library jars (using '-libraryjars').
  java.io.IOException: Please correct the above warnings first.
   at proguard.Initializer.execute(Initializer.java:321)
   at proguard.ProGuard.initialize(ProGuard.java:211)
   at proguard.ProGuard.execute(ProGuard.java:86)
   at proguard.ProGuard.main(ProGuard.java:492)
  </code></pre>
  
  <p>Each time I attempt to build I get different numbers of warnings (it's not very consistent). Also, when I perform a clean before export, the export completes without producing any warnings, but the resulting APK crashes on launch often due to <code>ClassNotFoundException</code>.</p>
  
  <p>My <code>proguard-project.txt</code> includes the necessary <code>-keep class</code> rules for the Android Support Library and ActionBarSherlock.</p>
  
  <p>I had no problems building this project before ADT 20. I even tried building my last release (which obviously built fine when I released it), but I get the same proguard warnings and failed export.</p>
  
  <p>I've tried adding <code>-libraryjars</code> and/or <code>-dontwarn</code> rules as many other SO questions suggest, but to no avail. It will sometimes build successfully, but the APK created crashes on launch.</p>
  
  <p>Any suggestions?</p>