DynamicHttpMetadataProvider's Regex "Metadata Request URL Construction Type" "Match" field

The "Match" field on the Common Attributes section of the DynamicHttpMetadataProvider appears to be required but is not marked with a red asterisk.

Steps to reproduce:
1. Log in
2. Add New -> Metadata Provider
3. Create a DynamicHttpMetadataProvider
4. On "2. Common Attributes", select "Regex" in the "Metadata Request URL Construction Type" dropdown
5. Enter a value for "Metadata Request URL Construction Value"
6. Leave "Match" blank

Note that at this point the form appears complete but it is not possible to advance to the next page. See attached screenshot for details.

7. Enter a value for "Match".

Note that you can now advance the form. Again, see attached screenshot.