refactor(router): ensure compatibility with noImplicitOverride (#42512)

Adds the `override` keyword to the `router` sources to ensure
compatibility with `noImplicitOverride`.

PR Close #42512

packages/router/src/events.ts

@@ -100,7 +100,7 @@ export class NavigationStart extends RouterEvent {
   }
 
   /** @docsNotRequired */
-  toString(): string {
+  override toString(): string {
     return `NavigationStart(id: ${this.id}, url: '${this.url}')`;
   }
 }
@@ -126,7 +126,7 @@ export class NavigationEnd extends RouterEvent {
   }
 
   /** @docsNotRequired */
-  toString(): string {
+  override toString(): string {
     return `NavigationEnd(id: ${this.id}, url: '${this.url}', urlAfterRedirects: '${
         this.urlAfterRedirects}')`;
   }
@@ -155,7 +155,7 @@ export class NavigationCancel extends RouterEvent {
   }
 
   /** @docsNotRequired */
-  toString(): string {
+  override toString(): string {
     return `NavigationCancel(id: ${this.id}, url: '${this.url}')`;
   }
 }
@@ -181,7 +181,7 @@ export class NavigationError extends RouterEvent {
   }
 
   /** @docsNotRequired */
-  toString(): string {
+  override toString(): string {
     return `NavigationError(id: ${this.id}, url: '${this.url}', error: ${this.error})`;
   }
 }
@@ -205,7 +205,7 @@ export class RoutesRecognized extends RouterEvent {
   }
 
   /** @docsNotRequired */
-  toString(): string {
+  override toString(): string {
     return `RoutesRecognized(id: ${this.id}, url: '${this.url}', urlAfterRedirects: '${
         this.urlAfterRedirects}', state: ${this.state})`;
   }
@@ -231,7 +231,7 @@ export class GuardsCheckStart extends RouterEvent {
     super(id, url);
   }
 
-  toString(): string {
+  override toString(): string {
     return `GuardsCheckStart(id: ${this.id}, url: '${this.url}', urlAfterRedirects: '${
         this.urlAfterRedirects}', state: ${this.state})`;
   }
@@ -259,7 +259,7 @@ export class GuardsCheckEnd extends RouterEvent {
     super(id, url);
   }
 
-  toString(): string {
+  override toString(): string {
     return `GuardsCheckEnd(id: ${this.id}, url: '${this.url}', urlAfterRedirects: '${
         this.urlAfterRedirects}', state: ${this.state}, shouldActivate: ${this.shouldActivate})`;
   }
@@ -288,7 +288,7 @@ export class ResolveStart extends RouterEvent {
     super(id, url);
   }
 
-  toString(): string {
+  override toString(): string {
     return `ResolveStart(id: ${this.id}, url: '${this.url}', urlAfterRedirects: '${
         this.urlAfterRedirects}', state: ${this.state})`;
   }
@@ -313,7 +313,7 @@ export class ResolveEnd extends RouterEvent {
     super(id, url);
   }
 
-  toString(): string {
+  override toString(): string {
     return `ResolveEnd(id: ${this.id}, url: '${this.url}', urlAfterRedirects: '${
         this.urlAfterRedirects}', state: ${this.state})`;
   }

packages/router/src/router_state.ts

@@ -59,7 +59,7 @@ export class RouterState extends Tree<ActivatedRoute> {
     setRouterState(<RouterState>this, root);
   }
 
-  toString(): string {
+  override toString(): string {
     return this.snapshot.toString();
   }
 }
@@ -421,7 +421,7 @@ export class RouterStateSnapshot extends Tree<ActivatedRouteSnapshot> {
     setRouterState(<RouterStateSnapshot>this, root);
   }
 
-  toString(): string {
+  override toString(): string {
     return serializeNode(this._root);
   }
 }