400 Errors Upon Creating Metadata Providers when space included (or otherwise invalid URL) for Metadata URL

Tested in version 1.0.1-SNAPSHOT-0479346
Description
When a user clicks the final Save button in creating a new metadata provider, the system simply continues loading. No error is given to the user. However, the Dev Tools provide a 400 Error.
 
Steps

1. Log into UI
2. Click 'Add New' button and select 'Metadata Provider’
3. On page 2 Common Attributes, enter a string that includes a space in the Metadata URL field
4. Move through the application to the final page filling in all required fields
5. Click 'Save'

What is occurring

Loading appears to not end. POST 400 Error in dev tools

What is expected

When user enters a Metadata URL that is invalid, a client-facing error should display. This url should be resolvable (not simply made-up).
A valid (format) url will not display an error, but if it is not resolved by the backend during saving of the provider, it will not throw an error in the UI. This is unspecified behavior at this time.

Valid metadata URL:

http://md.incommon.org/InCommon/InCommon-metadata.xml

Invalid examples:

google.com

Screenshot  

Screen Shot 2018-08-28 at 2.36.50 PM
 
Video Attached ProviderNotSaving
 
Error Code
Failed to load resource: the server responded with a status of 400 ()  
/api/MetadataResolvers:1
 
AND
 
VM165:1 POST https://shibboleth-ui.unicon.net/api/MetadataResolvers 400 ()
(anonymous) @ VM165:1
y @ polyfills.892972ba60a84bbdab39.js:1
t.scheduleTask @ polyfills.892972ba60a84bbdab39.js:1
onScheduleTask @ polyfills.892972ba60a84bbdab39.js:1
t.scheduleTask @ polyfills.892972ba60a84bbdab39.js:1 (continued in attached document)