Improper error message is displayed when clicking on upload button without selecting an archive

Following error message is displayed when a user clicks on 'Upload' button without selecting an archive.

'The following error occurred
Unsupported file type'

This error message should be changed to 'No Archive is selected to upload'.

Steps to reproduce:
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1. Log in to axis2 administration console
2. Click on 'Upload Service' in the left navigation pane
3. Click on upload button without specifying an archive

Actual Result:
==============
'The following error occurred
Unsupported file type' error message is displayed

Expected Result:
================
Error message should be changed to 'The following error occurred. No Archive is selected to upload'.