feature #36302 [Form] Add the html5 option to ColorType to validate the input (fancyweb)

This PR was merged into the 5.1-dev branch.

Discussion
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[Form] Add the html5 option to ColorType to validate the input

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Tickets       | no
| License       | MIT
| Doc PR        | TODO

Continuation of symfony/symfony#35626.

I'm resubmitting the initial implementation, this time in the Form component.

This `Color` constraint is dedicated to the HTML5 input type="color".

Commits
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454b6ff48b [Form] Add the html5 option to ColorType to validate the input

Author: fabpot

Resources/config/form.xml

@@ -74,6 +74,10 @@
             <tag name="form.type" />
             <argument type="service" id="translator" on-invalid="ignore" />
         </service>
+        <service id="form.type.color" class="Symfony\Component\Form\Extension\Core\Type\ColorType">
+            <tag name="form.type" />
+            <argument type="service" id="translator" on-invalid="ignore" />
+        </service>
 
         <service id="form.type_extension.form.transformation_failure_handling" class="Symfony\Component\Form\Extension\Core\Type\TransformationFailureExtension">
             <tag name="form.type_extension" extended-type="Symfony\Component\Form\Extension\Core\Type\FormType" />