Update avatar toolbar button when account is removed

Update the icon of the avatar toolbar button when
an account is signed out.
This happens for instance when the user selects cancel
on the sync-confirmation dialog.

Bug: 870656
Change-Id: Id557500c02ef2ac10d704cde75a9afe9db5e7655
Reviewed-on: https://chromium-review.googlesource.com/1185195Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Thomas Tangl <tangltom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585148}

chrome/browser/ui/views/profiles/avatar_toolbar_button.cc

@@ -176,6 +176,10 @@ void AvatarToolbarButton::OnAccountImageUpdated(const std::string& account_id,
   UpdateIcon();
 }
 
+void AvatarToolbarButton::OnAccountRemoved(const AccountInfo& info) {
+  UpdateIcon();
+}
+
 bool AvatarToolbarButton::IsIncognito() const {
   return profile_->IsOffTheRecord() && !profile_->IsGuestSession();
 }

chrome/browser/ui/views/profiles/avatar_toolbar_button.h

@@ -60,6 +60,7 @@ class AvatarToolbarButton : public ToolbarButton,
   // Needed if the first sync promo account should be displayed.
   void OnAccountImageUpdated(const std::string& account_id,
                              const gfx::Image& image) override;
+  void OnAccountRemoved(const AccountInfo& info) override;
 
   bool IsIncognito() const;
   bool ShouldShowGenericIcon() const;