fix(forms): Changed the TextValueAccessor to apply ng-touched on blur

[vultix]

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What is the current behavior?

The moment a TextField or TextView is touched the onTouched() function is called on the valueAccessor. This changes the ng-untouched class to ng-touched. See #1063 and Playground Demo

What is the new behavior?

The TextValueAccessor now waits for the blur event before marking the field as touched.

This is the angular-core behavior as can be seen here.

Fixes #1063, #804.

[ns-bot]

Can one of the admins verify this patch?

[ns-bot]

Can one of the admins verify this patch?

[ns-bot]

Can one of the admins verify this patch?

[gms1]

this PR would fix "TextField having wrong value if updateOn: 'blur'" 👍

https://github.com/angular/angular/blob/master/packages/forms/src/directives/control_value_accessor.ts
On blur (or equivalent), your class should call the registered function to allow
the forms API to update itself

[manoldonev]

test