[feat](emulators): add disableWarnings option

docs/emulators/emulators.md

@@ -129,4 +129,22 @@ import { SETTINGS as FIRESTORE_SETTINGS } from '@angular/fire/firestore';
 export class AppModule { }
 ```
 
+### 6.X.X Update
+
+By default, when serving an app with an active auth emulator, a warning message is displayed in the browser.
+This message can be disabled by providing an option with the auth emulator DI Token : 
+
+```ts
+import { USE_EMULATOR as USE_AUTH_EMULATOR } from '@angular/fire/auth';
+
+@NgModule({
+  // ... Existing configuration
+  providers: [
+    // ... Existing Providers
+    { provide: USE_AUTH_EMULATOR, useValue: environment.useEmulators ? ['localhost', 9099, {disableWarnings: true}] : undefined },
+  ]
+})
+export class AppModule { }
+```
+
 For older versions, please upgrade your app to latest version to get the advantages of these new features :rocket: 

src/auth/auth.ts

@@ -20,7 +20,7 @@ import { ɵfetchInstance } from '@angular/fire';
 
 export interface AngularFireAuth extends ɵPromiseProxy<firebase.auth.Auth> {}
 
-type UseEmulatorArguments = [string, number];
+type UseEmulatorArguments = [string, number, { disableWarnings: boolean }];
 export const USE_EMULATOR = new InjectionToken<UseEmulatorArguments>('angularfire2.auth.use-emulator');
 
 export const SETTINGS = new InjectionToken<firebase.auth.AuthSettings>('angularfire2.auth.settings');
@@ -89,7 +89,8 @@ export class AngularFireAuth {
           const auth = zone.runOutsideAngular(() => app.auth());
           if (useEmulator) {
             // Firebase Auth doesn't conform to the useEmulator convention, let's smooth that over
-            auth.useEmulator(`http://${useEmulator.join(':')}`);
+            const [url, port, options] = useEmulator;
+            auth.useEmulator(`http://${url}:${port}`, options);
           }
           if (tenantId) {
             auth.tenantId = tenantId;