Improve docs about exceptions through Binder.

Test: built

Change-Id: I5b6af61daa373c92f7d7b3b341a20fbd9e691da9
diff --git a/core/java/android/os/Binder.java b/core/java/android/os/Binder.java
index f45efda..0df6361 100644
--- a/core/java/android/os/Binder.java
+++ b/core/java/android/os/Binder.java
@@ -441,6 +441,11 @@
      *
      * <p>If you want to call this, call transact().
      *
+     * <p>Implementations that are returning a result should generally use
+     * {@link Parcel#writeNoException() Parcel.writeNoException} and
+     * {@link Parcel#writeException(Exception) Parcel.writeException} to propagate
+     * exceptions back to the caller.</p>
+     *
      * @param code The action to perform.  This should
      * be a number between {@link #FIRST_CALL_TRANSACTION} and
      * {@link #LAST_CALL_TRANSACTION}.
diff --git a/core/java/android/os/Parcel.java b/core/java/android/os/Parcel.java
index 10331b9..2efb0f5 100644
--- a/core/java/android/os/Parcel.java
+++ b/core/java/android/os/Parcel.java
@@ -1782,6 +1782,7 @@
      * <li>{@link IllegalStateException}
      * <li>{@link NullPointerException}
      * <li>{@link SecurityException}
+     * <li>{@link UnsupportedOperationException}
      * <li>{@link NetworkOnMainThreadException}
      * </ul>
      *