handle array length 0 correctly

Author: smnwttbr

Packages/com.unity.inputsystem/InputSystem/Editor/UITKAssetEditor/Views/CopyPasteHelper.cs

@@ -243,6 +243,9 @@ internal static void PasteItems(string copyBufferString, int[] indicesToInsert,
             // Split buffer into transmissions and then into transmission blocks
             var copiedType = GetCopiedType(copyBufferString);
             int indexOffset = 0;
+            // If the array is empty, make sure we insert at index 0
+            if(arrayToInsertInto.arraySize == 0)
+                indexOffset = -1;
             foreach (var transmission in copyBufferString.Substring(k_CopyPasteMarker.Length + k_TypeMarker[copiedType].Length)
                      .Split(new[] {k_EndOfTransmission}, StringSplitOptions.RemoveEmptyEntries))
             {