Added missing AutofillEventType so lint doesn't complain.

Test: In TreeHugger we trust!
Fixes: 68806712

Change-Id: I2f392161e71e0eca25a4a104b67e7d2982c90341

core/java/android/view/autofill/AutofillManager.java

@@ -1757,7 +1757,7 @@ public final class AutofillManager {
     public abstract static class AutofillCallback {
 
         /** @hide */
-        @IntDef({EVENT_INPUT_SHOWN, EVENT_INPUT_HIDDEN})
+        @IntDef({EVENT_INPUT_SHOWN, EVENT_INPUT_HIDDEN, EVENT_INPUT_UNAVAILABLE})
         @Retention(RetentionPolicy.SOURCE)
         public @interface AutofillEventType {}