[Signin] Remove a workaround in ProfileSigninConfirmationDialogViews

The workaround to hide the profile menu view before showing the
ProfileSigninConfirmationDialog is no longer needed. The dialog is now
modal on all platforms and takes the focus away from all other menus.

* Original bug: https://crbug.com/404711

Change-Id: I3b2dc4cfe2b0f8f36e8539ff6ee52024fe78b8df
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2386736
Auto-Submit: Alex Ilin <alexilin@chromium.org>
Reviewed-by: David Roger <droger@chromium.org>
Commit-Queue: David Roger <droger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#803419}

chrome/browser/ui/views/sync/profile_signin_confirmation_dialog_views.cc

@@ -109,15 +109,6 @@ void ProfileSigninConfirmationDialogViews::ShowDialog(
     Profile* profile,
     const std::string& username,
     std::unique_ptr<ui::ProfileSigninConfirmationDelegate> delegate) {
-  // Hides the new avatar bubble if it is currently shown. The new avatar bubble
-  // should be automatically closed when it loses focus. However on windows the
-  // profile signin confirmation dialog is not modal yet thus it does not take
-  // away focus, thus as a temporary workaround we need to manually close the
-  // bubble.
-  // TODO(guohui): removes the workaround once the profile confirmation dialog
-  // is fixed.
-  ProfileMenuView::Hide();
-
   // Checking whether to show the prompt is sometimes asynchronous. Defer
   // constructing the dialog (in ::Show) until that check completes.
   ui::CheckShouldPromptForNewProfile(