fix(material/icon): remove deprecated factory functions

Removes factory functions that we had marked as deprecated for v21. These functions aren't necessary since we switched to standalone.

BREAKING CHANGE:
* `ICON_REGISTRY_PROVIDER` has been removed.
* `ICON_REGISTRY_PROVIDER_FACTORY` has been removed.
* `MAT_ICON_LOCATION_FACTORY` has been removed.

Author: crisbeto

goldens/material/icon/index.api.md

@@ -15,7 +15,6 @@ import { InjectionToken } from '@angular/core';
 import { Observable } from 'rxjs';
 import { OnDestroy } from '@angular/core';
 import { OnInit } from '@angular/core';
-import { Optional } from '@angular/core';
 import { SafeHtml } from '@angular/platform-browser';
 import { SafeResourceUrl } from '@angular/platform-browser';
 
@@ -31,16 +30,6 @@ export function getMatIconNameNotFoundError(iconName: string): Error;
 // @public
 export function getMatIconNoHttpProviderError(): Error;
 
-// @public @deprecated
-export const ICON_REGISTRY_PROVIDER: {
-    provide: typeof MatIconRegistry;
-    deps: (Optional[] | typeof DomSanitizer | typeof ErrorHandler)[];
-    useFactory: typeof ICON_REGISTRY_PROVIDER_FACTORY;
-};
-
-// @public @deprecated
-export function ICON_REGISTRY_PROVIDER_FACTORY(parentRegistry: MatIconRegistry, httpClient: HttpClient, sanitizer: DomSanitizer, errorHandler: ErrorHandler, document?: any): MatIconRegistry;
-
 // @public
 export interface IconOptions {
     viewBox?: string;
@@ -56,9 +45,6 @@ export const MAT_ICON_DEFAULT_OPTIONS: InjectionToken<MatIconDefaultOptions>;
 // @public
 export const MAT_ICON_LOCATION: InjectionToken<MatIconLocation>;
 
-// @public @deprecated
-export function MAT_ICON_LOCATION_FACTORY(): MatIconLocation;
-
 // @public
 export class MatIcon implements OnInit, AfterViewChecked, OnDestroy {
     constructor(...args: unknown[]);

src/material/icon/icon-registry.ts

@@ -11,11 +11,9 @@ import {
   ErrorHandler,
   Inject,
   Injectable,
-  InjectionToken,
   OnDestroy,
   Optional,
   SecurityContext,
-  SkipSelf,
   DOCUMENT,
 } from '@angular/core';
 import {DomSanitizer, SafeHtml, SafeResourceUrl} from '@angular/platform-browser';
@@ -728,39 +726,6 @@ export class MatIconRegistry implements OnDestroy {
   }
 }
 
-/**
- * @docs-private
- * @deprecated No longer used, will be removed.
- * @breaking-change 21.0.0
- */
-export function ICON_REGISTRY_PROVIDER_FACTORY(
-  parentRegistry: MatIconRegistry,
-  httpClient: HttpClient,
-  sanitizer: DomSanitizer,
-  errorHandler: ErrorHandler,
-  document?: any,
-) {
-  return parentRegistry || new MatIconRegistry(httpClient, sanitizer, document, errorHandler);
-}
-
-/**
- * @docs-private
- * @deprecated No longer used, will be removed.
- * @breaking-change 21.0.0
- */
-export const ICON_REGISTRY_PROVIDER = {
-  // If there is already an MatIconRegistry available, use that. Otherwise, provide a new one.
-  provide: MatIconRegistry,
-  deps: [
-    [new Optional(), new SkipSelf(), MatIconRegistry],
-    [new Optional(), HttpClient],
-    DomSanitizer,
-    ErrorHandler,
-    [new Optional(), DOCUMENT as InjectionToken<any>],
-  ],
-  useFactory: ICON_REGISTRY_PROVIDER_FACTORY,
-};
-
 /** Clones an SVGElement while preserving type information. */
 function cloneSvg(svg: SVGElement): SVGElement {
   return svg.cloneNode(true) as SVGElement;

src/material/icon/icon.ts

@@ -54,7 +54,16 @@ export const MAT_ICON_DEFAULT_OPTIONS = new InjectionToken<MatIconDefaultOptions
  */
 export const MAT_ICON_LOCATION = new InjectionToken<MatIconLocation>('mat-icon-location', {
   providedIn: 'root',
-  factory: MAT_ICON_LOCATION_FACTORY,
+  factory: () => {
+    const _document = inject(DOCUMENT);
+    const _location = _document ? _document.location : null;
+
+    return {
+      // Note that this needs to be a function, rather than a property, because Angular
+      // will only resolve it once, but we want the current path on each call.
+      getPathname: () => (_location ? _location.pathname + _location.search : ''),
+    };
+  },
 });
 
 /**
@@ -65,22 +74,6 @@ export interface MatIconLocation {
   getPathname: () => string;
 }
 
-/**
- * @docs-private
- * @deprecated No longer used, will be removed.
- * @breaking-change 21.0.0
- */
-export function MAT_ICON_LOCATION_FACTORY(): MatIconLocation {
-  const _document = inject(DOCUMENT);
-  const _location = _document ? _document.location : null;
-
-  return {
-    // Note that this needs to be a function, rather than a property, because Angular
-    // will only resolve it once, but we want the current path on each call.
-    getPathname: () => (_location ? _location.pathname + _location.search : ''),
-  };
-}
-
 /** SVG attributes that accept a FuncIRI (e.g. `url(<something>)`). */
 const funcIriAttributes = [
   'clip-path',