docs: add di-related api doc (#27731)

PR Close #27731

packages/common/src/location/location_strategy.ts

@@ -40,16 +40,15 @@ export abstract class LocationStrategy {
 
 
 /**
- * The `APP_BASE_HREF` token represents the base href to be used with the
- * {@link PathLocationStrategy}.
- *
- * If you're using {@link PathLocationStrategy}, you must provide a provider to a string
- * representing the URL prefix that should be preserved when generating and recognizing
- * URLs.
+ * A predefined [DI token](guide/glossary#di-token) for the base href
+ * to be used with the `PathLocationStrategy`.
+ * The base href is the URL prefix that should be preserved when generating
+ * and recognizing URLs.
  *
  * @usageNotes
  *
- * ### Example
+ * The following example shows how to use this token to configure the root app injector
+ * with a base href value, so that the DI framework can supply the dependency anywhere in the app.
  *
  * ```typescript
  * import {Component, NgModule} from '@angular/core';