Ability to set variant machine name in Panels UI for Cloning and Importing variants.

Problem/Motivation

Follow-up to #813754: Ability to set variant machine name in Panels UI →

Ability to set variant machine name in Panels UI for Cloning and Importing variants.

→

Proposed resolution

Explicitly set a machine-name when importing and cloning variants.

Behaviour Variant Clone

• When using an existing machine_name, you get a validation error before saving. Message is something like "The machine-readable name is already in use. It must be unique."

Behaviour Variant Import

• When using an existing machine_name + option 'Overwrite=FALSE', you get a validation error before saving. Message is something like "The machine-readable name is already in use. It must be unique."
• When using an existing machine_name + option 'Overwrite=TRUE', the existing variant will be deleted before saving the new variant. No errors.
• When using an non-existing machine_name + option 'Overwrite=FALSE', the new variant will be saved.
• When using an non-existing machine_name + option 'Overwrite=TRUE', the new variant will be saved.

Additional behaviour Variant Import regarding UUID's

• Re-generate UUIDs if machine-name is different than import-code.
• Keep UUIDs of import-code if machine-name is equal than import-code.

Remaining tasks

User interface changes

• Machine-name field and overwrite checkbox added to panel-variant import-form.
• Machine-name field added to panel-variant clone-form.

API changes

• none