feat(core): remove ViewEncapsulation.Native (#38882)

Removes `ViewEncapsulation.Native` which has been deprecated for several major versions.

BREAKING CHANGES:
* `ViewEncapsulation.Native` has been removed. Use `ViewEncapsulation.ShadowDom` instead. Existing
usages will be updated automatically by `ng update`.

PR Close #38882

packages/compiler/src/compiler_facade_interface.ts

@@ -173,7 +173,7 @@ export interface R3FactoryDefMetadataFacade {
 
 export enum ViewEncapsulation {
   Emulated = 0,
-  Native = 1,
+  // Historically the 1 value was for `Native` encapsulation which has been removed as of v11.
   None = 2,
   ShadowDom = 3
 }

packages/compiler/src/core.ts

@@ -82,7 +82,7 @@ export interface Component extends Directive {
 }
 export enum ViewEncapsulation {
   Emulated = 0,
-  Native = 1,
+  // Historically the 1 value was for `Native` encapsulation which has been removed as of v11.
   None = 2,
   ShadowDom = 3
 }

packages/compiler/src/render3/view/api.ts

@@ -163,8 +163,6 @@ export interface R3ComponentMetadata extends R3DirectiveMetadata {
 
   /**
    * An encapsulation policy for the template and CSS styles. One of:
-   * - `ViewEncapsulation.Native`: Use shadow roots. This works only if natively available on the
-   *   platform (note that this is marked the as the "deprecated shadow DOM" as of Angular v6.1.
    * - `ViewEncapsulation.Emulated`: Use shimmed CSS that emulates the native behavior.
    * - `ViewEncapsulation.None`: Use global CSS without any encapsulation.
    * - `ViewEncapsulation.ShadowDom`: Use the latest ShadowDOM API to natively encapsulate styles

packages/compiler/test/directive_normalizer_spec.ts

@@ -226,7 +226,7 @@ function normalizeTemplate(normalizer: DirectiveNormalizer, o: {
     describe('normalizeLoadedTemplate', () => {
       it('should store the viewEncapsulation in the result',
          inject([DirectiveNormalizer], (normalizer: DirectiveNormalizer) => {
-           const viewEncapsulation = ViewEncapsulation.Native;
+           const viewEncapsulation = ViewEncapsulation.ShadowDom;
            const template = <CompileTemplateMetadata>normalizeTemplate(normalizer, {
              encapsulation: viewEncapsulation,
              template: '',