Make ProGuard keep necessary members for serializable classes

@com.google.common.annotations.VisibleForTesting *;

}

# Keep serializable classes and necessary members for serializable classes

# Copied from the ProGuard manual at http://proguard.sourceforge.net.

-keepnames class * implements java.io.Serializable

-keepclassmembers class * implements java.io.Serializable {

    static final long serialVersionUID;

    private static final java.io.ObjectStreamField[] serialPersistentFields;

    !static !transient <fields>;

    private void writeObject(java.io.ObjectOutputStream);

    private void readObject(java.io.ObjectInputStream);

    java.lang.Object writeReplace();

    java.lang.Object readResolve();

}

# Please specify classes to be kept explicitly in your package's configuration.

# -keep class * extends android.app.Activity

# -keep class * extends android.view.View