Make a documented annotation.
We want methods annotated with to include it in their javadoc.
package com.google.firebase.annotations;
+import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Target;
@@ -23,4 +24,5 @@ import java.lang.annotation.Target;
* API stability or backward-compatibility.
*/
@Target({ElementType.TYPE, ElementType.FIELD, ElementType.METHOD, ElementType.CONSTRUCTOR})
+@Documented
public @interface PreviewApi {}
