External validation errors are not shown instantly

**I have the following setup:**
paper-form with paper-input elements. The errors property of the paper-input elements is set to model.validations.attrs.[field].messages. Validation is done with ember-cp-validations. This works fine so far with on exception: For one field the validation is done with the ds-error validator to validate error message from the server.

**This leads to the following problem:**
If I submit the form, the error message gets serialized correctly and even the paper-input method has the error property set BUT it is not shown, as the paper-input element is treated as untouched after submit. I have to first blur on the element to get the error message shown. I would expect this message to be visible instantly.

Reproduce the issue with paper-form, paper-input, and ember-cp-validations, using a server-side ds-error validation after form submission. Inspect how submission updates the input's touched state and how the errors property is rendered. Done means the serialized validation message is visible immediately after submit, without requiring a blur.

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