Just kidding, keep proposed onDidChangeAuthenticationProviders API for now

src/vs/vscode.proposed.d.ts

@@ -135,6 +135,12 @@ declare module 'vscode' {
 		 */
 		export function registerAuthenticationProvider(provider: AuthenticationProvider): Disposable;
 
+		/**
+		 * @deprecated - getSession should now trigger extension activation.
+		 * Fires with the provider id that was registered or unregistered.
+		 */
+		export const onDidChangeAuthenticationProviders: Event<AuthenticationProvidersChangeEvent>;
+
 		/**
 		 * An array of the information of authentication providers that are currently registered.
 		 */

src/vs/workbench/api/common/extHost.api.impl.ts

@@ -219,14 +219,6 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 				checkProposedApiEnabled(extension);
 				return extHostAuthentication.onDidChangeAuthenticationProviders;
 			},
-			getProviderIds(): Thenable<ReadonlyArray<string>> {
-				checkProposedApiEnabled(extension);
-				return extHostAuthentication.getProviderIds();
-			},
-			get providerIds(): string[] {
-				checkProposedApiEnabled(extension);
-				return extHostAuthentication.providerIds;
-			},
 			get providers(): ReadonlyArray<vscode.AuthenticationProviderInformation> {
 				checkProposedApiEnabled(extension);
 				return extHostAuthentication.providers;

src/vs/workbench/api/common/extHostAuthentication.ts

@@ -43,14 +43,6 @@ export class ExtHostAuthentication implements ExtHostAuthenticationShape {
 		return Promise.resolve();
 	}
 
-	getProviderIds(): Promise<ReadonlyArray<string>> {
-		return this._proxy.$getProviderIds();
-	}
-
-	get providerIds(): string[] {
-		return this._providerIds;
-	}
-
 	get providers(): ReadonlyArray<vscode.AuthenticationProviderInformation> {
 		return Object.freeze(this._providers.slice());
 	}