Add clone() method support for nano.

Upstreamed from Another Place (cr/57247854).

Change-Id: I2aaf59544c0f5ae21a51891d8a5eeda1dc722c90

1 files changed, 8 insertions, 0 deletions

diff --git a/javanano/src/main/java/com/google/protobuf/nano/InternalNano.java b/javanano/src/main/java/com/google/protobuf/nano/InternalNano.java
index e7ba8d12..f1263df5 100644
--- a/javanano/src/main/java/com/google/protobuf/nano/InternalNano.java
+++ b/javanano/src/main/java/com/google/protobuf/nano/InternalNano.java
@@ -536,4 +536,12 @@ public final class InternalNano {
     }
     return o.hashCode();
   }
+
+  // This avoids having to make FieldArray public.
+  public static void cloneUnknownFieldData(ExtendableMessageNano original,
+      ExtendableMessageNano cloned) {
+    if (original.unknownFieldData != null) {
+      cloned.unknownFieldData = (FieldArray) original.unknownFieldData.clone();
+    }
+  }
 }