Align the behavior of returning Byte[] and returning byte[]
diff --git a/third_party/sl4a/src/main/java/com/google/android/mobly/snippet/rpc/JsonBuilder.java b/third_party/sl4a/src/main/java/com/google/android/mobly/snippet/rpc/JsonBuilder.java
index f543b62..f996fce 100644
--- a/third_party/sl4a/src/main/java/com/google/android/mobly/snippet/rpc/JsonBuilder.java
+++ b/third_party/sl4a/src/main/java/com/google/android/mobly/snippet/rpc/JsonBuilder.java
@@ -40,6 +40,9 @@
         if (data == null) {
             return JSONObject.NULL;
         }
+        if (data instanceof Byte) {
+            return (Byte) data & 0xFF;
+        }
         if (data instanceof Integer) {
             return data;
         }