[ermine] Update e2e smoke test

Updates the smoke test for ermine after modular -> sfw transition.
The test previously assumed a base shell existed, which is not
true anymore.

This is still blocked on http://fxb/44506

Build: fx set workstation.x64 --args=flutter_driver_enabled=true
Test: fx run-e2e-tests experiences_ermine_session_shell_e2e_test
Change-Id: Ia8b91c233f27aa5862c78e7895b14a08a39fca41
diff --git a/tests/e2e/test/ermine_smoke_test.dart b/tests/e2e/test/ermine_smoke_test.dart
index e0096eb..f0e6967 100644
--- a/tests/e2e/test/ermine_smoke_test.dart
+++ b/tests/e2e/test/ermine_smoke_test.dart
@@ -27,59 +27,34 @@
     connector = FlutterDriverConnector(sl4f);
     await connector.initialize();
 
-    // Check if base shell is running.
-    final isolate = await connector.isolate('userpicker_base_shell');
+    // Check if ermine is running.
+    final isolate = await connector.isolate('ermine');
     if (isolate == null) {
-      fail('could not find userpicker_base_shell.');
+      fail('could not find ermine.');
     }
 
-    // Now connect to base shell.
-    driver = await connector.driverForIsolate('userpicker_base_shell');
+    // Now connect to ermine.
+    driver = await connector.driverForIsolate('ermine');
     if (driver == null) {
-      fail('unable to connect to userpicker_base_shell.');
+      fail('unable to connect to ermine.');
     }
   });
 
   tearDownAll(() async {
-    await driver.close();
+    await driver?.close();
     await connector.tearDown();
     await sl4f.stopServer();
     sl4f.close();
   });
 
-  test('Guest login to ermine', () async {
-    // Get the center of the plus key.
-    final plusButtonFinder = find.byValueKey('plus');
-    var center = await centerFromFinder(driver, plusButtonFinder);
-
-    final input = Input(sl4f);
-    bool didTap = await input.tap(Point(center.x, center.y));
-    expect(didTap, true);
-
-    // The 'Guest' button should be visible, tap it.
-    final guestButtonFinder = find.byValueKey('Guest');
-    center = await centerFromFinder(driver, guestButtonFinder);
-
-    didTap = await input.tap(Point(center.x, center.y));
-    expect(didTap, true);
-
-    // This should launch ermine.
-    final ermineDriver = await connector.driverForIsolate('ermine');
-    if (ermineDriver == null) {
-      fail('Unable to launch ermine');
-    }
-    await ermineDriver.waitUntilNoTransientCallbacks();
+  test('Screen should not be black', () async {
+    await driver.waitUntilNoTransientCallbacks();
 
     // Now take a screen shot and make sure it is not all black.
     final scenic = Scenic(sl4f);
     final image = await scenic.takeScreenshot();
     bool isAllBlack = image.data.every((pixel) => pixel & 0x00ffffff == 0);
     expect(isAllBlack, false);
-
-    // Now log out of ermine.
-    final logoutFinder = find.byValueKey('logout');
-    await ermineDriver.tap(logoutFinder);
-    await ermineDriver.close();
   });
 }