Clarify that @crv, when applied to a class, includes methods on inner…

… classes.

I didn't think this was super obvious from the Javadoc; I wound up reading the implementation to check.

PiperOrigin-RevId: 428869499

annotations/src/main/java/com/google/errorprone/annotations/CheckReturnValue.java

@@ -31,9 +31,9 @@
  * when one of these methods is called but the result is not used.
  *
  * <p>{@code @CheckReturnValue} may be applied to a class or package to indicate that all methods in
- * that class or package must have their return values checked. For convenience, we provide an
- * annotation, {@link CanIgnoreReturnValue}, to exempt specific methods or classes from this
- * behavior.
+ * that class (including indirectly; that is, methods of inner classes within the annotated class)
+ * or package must have their return values checked. For convenience, we provide an annotation,
+ * {@link CanIgnoreReturnValue}, to exempt specific methods or classes from this behavior.
  */
 @Documented
 @Target({METHOD, CONSTRUCTOR, TYPE, PACKAGE})