Pipeline Studio - User need to be able to choose to either save or cancel any changes to the plugin properties

As a CDAP User, I need to be able to "cancel" any action I have performed while editing the properties (including the schema) of a plugin.
Currently, the only actions supported are to [Validate] or to click on [x] which closes and saves the changes.
This is problematic in many ways:

• Everywhere else in CDAP when the user selects a [x] icon, the behavior equals to a [cancel]: none of the changes are committed

• We don't give any meaningful way for the user to undo many of the changes.

• UX best practices ask for giving the user a "way out" by including some form of [cancel] behaviour.

• Most users think that the current behaviour is an 'autosave', although this is not how it is handled in the backend.

•  

[design needed]