List of certain user flagged nodes in a view
1) Create a Node View   

2) Add a relationship Flags: Node flag (select the required flags and tick "Include only tagged Nodes"   

3) Add another Relationship Flags : User (use the above relationship on this)   

4) Add Argument User ID (named Contextual Filters in Drupal 7) and use the relationship "Flags : User"

5) Add the required fields.