feat(auth): Added support for Android private browsing (#6336)

* Added support for setEphemeralBrowsingEnabled

* Updated Auth Android unit test

Author: tyllark

packages/auth/amplify_auth_cognito/android/src/main/kotlin/com/amazonaws/amplify/amplify_auth_cognito/AmplifyAuthCognitoPlugin.kt

@@ -433,11 +433,12 @@ open class AmplifyAuthCognitoPlugin :
   /**
    * Launches [url] in a Custom Tab.
    */
-  open fun launchUrl(url: String, browserPackageName: String?) {
+  open fun launchUrl(url: String, browserPackageName: String?, preferPrivateSession: Boolean) {
     if (mainActivity == null) {
       throw HostedUiException.UNKNOWN("No activity found")
     }
     val intent = CustomTabsIntent.Builder().apply {
+      setEphemeralBrowsingEnabled(preferPrivateSession)
       setShareState(CustomTabsIntent.SHARE_STATE_OFF)
     }.build()
     val useBrowserPackage = browserPackageName
@@ -469,9 +470,6 @@ open class AmplifyAuthCognitoPlugin :
 
   /**
    * Launch the sign in URL.
-   *
-   * Note: [preferPrivateSession] currently has no effect on Android since it is not supported in
-   * custom tabs.
    */
   override fun signInWithUrl(
     url: String,
@@ -482,7 +480,7 @@ open class AmplifyAuthCognitoPlugin :
   ) {
     val result = AtomicResult(callback, "signIn")
     try {
-      launchUrl(url, browserPackageName)
+      launchUrl(url, browserPackageName, preferPrivateSession)
       signInResult = result
     } catch (e: Throwable) {
       result(Result.failure(HostedUiException.fromThrowable(e)))
@@ -501,7 +499,7 @@ open class AmplifyAuthCognitoPlugin :
   ) {
     val result = AtomicResult(callback, "signOut")
     try {
-      launchUrl(url, browserPackageName)
+      launchUrl(url, browserPackageName, preferPrivateSession)
       signOutResult = result
     } catch (e: Throwable) {
       result(Result.failure(HostedUiException.fromThrowable(e)))

packages/auth/amplify_auth_cognito/android/src/test/kotlin/com/amazonaws/amplify/amplify_auth_cognito/AmplifyAuthCognitoPluginTest.kt

@@ -32,7 +32,7 @@ internal class AmplifyAuthCognitoPluginTest {
     @Test
     fun convertsCancelledException() {
         val mockPlugin = object : AmplifyAuthCognitoPlugin() {
-            override fun launchUrl(url: String, browserPackageName: String?) {
+            override fun launchUrl(url: String, browserPackageName: String?, preferPrivateSession: Boolean) {
                 throw HostedUiException.CANCELLED()
             }
         }
@@ -70,7 +70,7 @@ internal class AmplifyAuthCognitoPluginTest {
     fun convertsUnknownException() {
         val aMessage = "a message"
         val mockPlugin = object : AmplifyAuthCognitoPlugin() {
-            override fun launchUrl(url: String, browserPackageName: String?) {
+            override fun launchUrl(url: String, browserPackageName: String?, preferPrivateSession: Boolean) {
                 throw HostedUiException.UNKNOWN(aMessage)
             }
         }

packages/auth/amplify_auth_cognito_dart/lib/src/model/signin/cognito_sign_in_with_web_ui_plugin_options.dart

@@ -22,12 +22,14 @@ class CognitoSignInWithWebUIPluginOptions extends SignInWithWebUIPluginOptions {
   ) => _$CognitoSignInWithWebUIPluginOptionsFromJson(json);
 
   /// {@template amplify_auth_cognito.model.cognito_sign_in_with_web_ui_options.private_session}
-  /// iOS-only: Starts the webUI signin in a private browser session, if supported by the current browser.
+  /// Starts the webUI signin in a private browser session, if supported by the current browser.
   ///
-  /// Note that this value internally sets `prefersEphemeralWebBrowserSession` in ASWebAuthenticationSession.
+  /// Note that on iOS this value internally sets `prefersEphemeralWebBrowserSession` in ASWebAuthenticationSession.
   /// As per Apple documentation, Whether the request is honored depends on the user’s default web browser.
   /// Safari always honors the request.
   ///
+  /// Note that on Android this value internally sets `setEphemeralBrowsingEnabled` in CustomTabsIntent.
+  ///
   /// Defaults to `false`.
   /// {@endtemplate}
   final bool isPreferPrivateSession;