Choosing a project while forking a repository cause Java error in Bitbucket 6.1.0 when personal repositories feature is disabled

Issue Summary

In Bitbucket Server version 6.1.0, as similar to bug BSERV-11622 but with personal repository feature is disabled. Upon choosing a different project and attempt to fork the repository cause Java error.

Environment

• Bitbucket Server ver6.1.0
• Tested OS - Windows 10 Pro & Ubuntu 16.04 LTS
• Tested Database - Bundle DB H2 and MySQL
• Personal Repository feature is disabled.

Steps to Reproduce

1. Disable Personal Repository feature by adding the following line to bitbucket.properties:

   feature.personal.repos=false
   

2. Restart the Bitbucket Server.
3. Create two different project called project-01 and project-02
4. Create a repository called repo-01 in project-01 and populate repo-01 with files.
5. Fork the repo-01 to project-02 - Go to forks -> Create fork
6. Select the project-02 in Fork creation screen
7. Click 'Fork repository'

Expected Results

A fork is created in the project selected.

Actual Results

Fork funtion throwing errors:

Notes

• The log file did not show any related trace.
• HAR file does not provide much info as well.

(Optional - If Necessary)

Workaround

Required, if there is no workaround please state:
Currently there is no known workaround for this behavior. A workaround will be added here when available