Fix docs on gpr_slice_unref.
diff --git a/include/grpc/support/slice.h b/include/grpc/support/slice.h
index 9026602..3ee103b 100644
--- a/include/grpc/support/slice.h
+++ b/include/grpc/support/slice.h
@@ -110,8 +110,9 @@
/* Decrement the ref count of s. If the ref count of s reaches zero, all
slices sharing the ref count are destroyed, and considered no longer
initialized. If s is ultimately derived from a call to gpr_slice_new(start,
- len, dest) where dest!=NULL , then (*dest)(start, len) is called. Requires
- s initialized. */
+ len, dest) where dest!=NULL , then (*dest)(start) is called, else if s is
+ ultimately derived from a call to gpr_slice_new_with_len(start, len, dest)
+ where dest!=NULL , then (*dest)(start, len). Requires s initialized. */
void gpr_slice_unref(gpr_slice s);
/* Create a slice pointing at some data. Calls malloc to allocate a refcount