/locate and custom worlds

If you use /locate in a custom world with some structures disabled it still gives the location of the nonexistent structure.

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^{Mod edit: Copied repro steps from MC-130441}

Expected output:

'Could not find that structure nearby.' (or whatever the command says when it fails)

Returned output:

'The nearest <structure> is [coords].'

The bug

The /locate command returns coordinates of structures even in worlds when structure generation is disabled.

To recreate

1. Create a new world where generate-structures=false.
2. Use /locate <structure> and observe the output.
3. Click the coordinates to travel there.
4. There is no structure because structure generation is disabled.
5. Command should output there is no structure nearby.