[iOS] Manage sync should not commit sync when being closed

When kMobileIdentityConsistency flag is disabled, the sync should be
confirmed or disabled by GoogleServicesCoordinator.

Bug introduced: crrev.com/c/2463306

Fixed: 1141961
Change-Id: I2bd01a0c43458758f0088a17594bf5291900c510
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2498525
Commit-Queue: Jérôme Lebel <jlebel@chromium.org>
Reviewed-by: Nohemi Fernandez <fernandex@chromium.org>
Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821317}

ios/chrome/browser/ui/settings/google_services/google_services_settings_egtest.mm

@@ -35,6 +35,8 @@ using chrome_test_util::AddAccountButton;
 using chrome_test_util::ButtonWithAccessibilityLabelId;
 using chrome_test_util::GoogleServicesSettingsButton;
 using chrome_test_util::SettingsDoneButton;
+using chrome_test_util::SettingsMenuBackButton;
+using chrome_test_util::SyncSettingsConfirmButton;
 
 // Integration tests using the Google services settings screen.
 @interface GoogleServicesSettingsTestCase : ChromeTestCase
@@ -349,6 +351,47 @@ using chrome_test_util::SettingsDoneButton;
       @"Failed to toggle-on password leak checks");
 }
 
+// Tests the following steps:
+//  + Opens sign-in from Google services
+//  + Taps on the settings link to open the advanced sign-in settings
+//  + Opens "Manage Sync" twice
+// The "Manage Sync" should not be disabled when closing "Manage Sync" view.
+- (void)testOpenManageSyncSettings {
+  FakeChromeIdentity* fakeIdentity = [SigninEarlGrey fakeIdentity1];
+  [SigninEarlGrey addFakeIdentity:fakeIdentity];
+
+  [ChromeEarlGreyUI openSettingsMenu];
+  [ChromeEarlGreyUI
+      tapSettingsMenuButton:chrome_test_util::PrimarySignInButton()];
+  [SigninEarlGreyUI tapSettingsLink];
+  // Open "Manage Sync" settings.
+  id<GREYMatcher> manageSyncMatcher =
+      [self cellMatcherWithTitleID:IDS_IOS_MANAGE_SYNC_SETTINGS_TITLE
+                      detailTextID:0];
+  [[EarlGrey selectElementWithMatcher:manageSyncMatcher]
+      performAction:grey_tap()];
+
+  id<GREYMatcher> backButtonMatcher =
+      grey_allOf(SettingsMenuBackButton(),
+                 grey_descendant(grey_kindOfClass([UIImageView class])), nil);
+  // Back to the Google services settings view.
+  [[EarlGrey selectElementWithMatcher:backButtonMatcher]
+      performAction:grey_tap()];
+  // Open "Manage Sync" settings, again.
+  [[EarlGrey selectElementWithMatcher:manageSyncMatcher]
+      performAction:grey_tap()];
+  // Back to the Google services settings view.
+  [[EarlGrey selectElementWithMatcher:backButtonMatcher]
+      performAction:grey_tap()];
+
+  // Close the advance settings.
+  [[EarlGrey selectElementWithMatcher:SyncSettingsConfirmButton()]
+      performAction:grey_tap()];
+
+  // Test the user is signed in.
+  [SigninEarlGrey verifySignedInWithFakeIdentity:fakeIdentity];
+}
+
 #pragma mark - Helpers
 
 // Opens the Google services settings.

ios/chrome/browser/ui/settings/google_services/manage_sync_settings_coordinator.mm

@@ -113,9 +113,16 @@ using signin_metrics::PromoAction;
 }
 
 - (void)stop {
+  // If kMobileIdentityConsistency is disabled,
+  // GoogleServicesSettingsCoordinator is in charge to enable sync or not when
+  // being closed. This coordinator displays a sub view.
+  // With kMobileIdentityConsistency enabled:
+  // This coordinator displays the main view and it is in charge to enable sync
+  // or not when being closed.
   // Sync changes should only be commited if the user is authenticated and
   // the sign-in has not been interrupted.
-  if (self.authService->IsAuthenticated() || !self.signinInterrupted) {
+  if (base::FeatureList::IsEnabled(signin::kMobileIdentityConsistency) &&
+      (self.authService->IsAuthenticated() || !self.signinInterrupted)) {
     SyncSetupService* syncSetupService =
         SyncSetupServiceFactory::GetForBrowserState(
             self.browser->GetBrowserState());