docs(forms): migrate deprecated @howToUse tags (#23186)

In this case they have been converted to `@description` tags.

PR Close #23186

packages/forms/src/directives/ng_form.ts

@@ -29,7 +29,7 @@ const resolvedPromise = Promise.resolve(null);
  * @whatItDoes Creates a top-level {@link FormGroup} instance and binds it to a form
  * to track aggregate form value and validation status.
  *
- * @howToUse
+ * @description
  *
  * As soon as you import the `FormsModule`, this directive becomes active by default on
  * all `<form>` tags.  You don't need to add a special selector.

packages/forms/src/directives/ng_model.ts

@@ -54,7 +54,7 @@ const resolvedPromise = Promise.resolve(null);
  * within a parent form, the directive will also register itself with the form as a child
  * control.
  *
- * @howToUse
+ * @description
  *
  * This directive can be used by itself or as part of a larger form. All you need is the
  * `ngModel` selector to activate it.

packages/forms/src/directives/ng_model_group.ts

@@ -23,7 +23,7 @@ export const modelGroupProvider: any = {
 /**
  * @whatItDoes Creates and binds a {@link FormGroup} instance to a DOM element.
  *
- * @howToUse
+ * @description
  *
  * This directive can only be used as a child of {@link NgForm} (or in other words,
  * within `<form>` tags).

packages/forms/src/directives/radio_control_value_accessor.ts

@@ -60,7 +60,7 @@ export class RadioControlRegistry {
  * Used by {@link NgModel}, {@link FormControlDirective}, and {@link FormControlName}
  * to keep the view synced with the {@link FormControl} model.
  *
- * @howToUse
+ * @description
  *
  * If you have imported the {@link FormsModule} or the {@link ReactiveFormsModule}, this
  * value accessor will be active on any radio control that has a form directive. You do

packages/forms/src/directives/reactive_directives/form_control_directive.ts

@@ -36,7 +36,7 @@ export const formControlBinding: any = {
  * any values written to the DOM element through user input will be reflected in the
  * {@link FormControl} instance (view -> model).
  *
- * @howToUse
+ * @description
  *
  * Use this directive if you'd like to create and manage a {@link FormControl} instance directly.
  * Simply create a {@link FormControl}, save it to your component class, and pass it into the

packages/forms/src/directives/reactive_directives/form_control_name.ts

@@ -36,7 +36,7 @@ export const controlNameBinding: any = {
  * any values written to the DOM element through user input will be reflected in the
  * {@link FormControl} instance (view -> model).
  *
- * @howToUse
+ * @description
  *
  * This directive is designed to be used with a parent {@link FormGroupDirective} (selector:
  * `[formGroup]`).

packages/forms/src/directives/reactive_directives/form_group_directive.ts

@@ -25,7 +25,7 @@ export const formDirectiveProvider: any = {
 /**
  * @whatItDoes Binds an existing {@link FormGroup} to a DOM element.
  *
- * @howToUse
+ * @description
  *
  * This directive accepts an existing {@link FormGroup} instance. It will then use this
  * {@link FormGroup} instance to match any child {@link FormControl}, {@link FormGroup},

packages/forms/src/directives/reactive_directives/form_group_name.ts

@@ -26,7 +26,7 @@ export const formGroupNameProvider: any = {
 /**
  * @whatItDoes Syncs a nested {@link FormGroup} to a DOM element.
  *
- * @howToUse
+ * @description
  *
  * This directive can only be used with a parent {@link FormGroupDirective} (selector:
  * `[formGroup]`).
@@ -97,7 +97,7 @@ export const formArrayNameProvider: any = {
 /**
  * @whatItDoes Syncs a nested {@link FormArray} to a DOM element.
  *
- * @howToUse
+ * @description
  *
  * This directive is designed to be used with a parent {@link FormGroupDirective} (selector:
  * `[formGroup]`).

packages/forms/src/directives/select_control_value_accessor.ts

@@ -32,7 +32,7 @@ function _extractId(valueString: string): string {
  * Used by {@link NgModel}, {@link FormControlDirective}, and {@link FormControlName}
  * to keep the view synced with the {@link FormControl} model.
  *
- * @howToUse
+ * @description
  *
  * If you have imported the {@link FormsModule} or the {@link ReactiveFormsModule}, this
  * value accessor will be active on any select control that has a form directive. You do
@@ -160,7 +160,7 @@ export class SelectControlValueAccessor implements ControlValueAccessor {
 /**
  * @whatItDoes Marks `<option>` as dynamic, so Angular can be notified when options change.
  *
- * @howToUse
+ * @description
  *
  * See docs for {@link SelectControlValueAccessor} for usage examples.
  *