Fix sync error updates for avatar button

When the sync error state changes from one error
to another, the AvatarToolbarButton was not updated.
This CL fixes this.

Bug: 881874
Change-Id: I247cf12a18f8122a22b2d51dd5e6f1febdd6f432
Reviewed-on: https://chromium-review.googlesource.com/1215864Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Thomas Tangl <tangltom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589894}

chrome/browser/ui/avatar_button_error_controller.cc

@@ -30,10 +30,9 @@ void AvatarButtonErrorController::UpdateSigninError(bool has_signin_error) {
 }
 
 void AvatarButtonErrorController::UpdateSyncError(bool has_sync_error) {
-  bool had_error = HasAvatarError();
   has_sync_error_ = has_sync_error;
-  if (had_error != HasAvatarError())
-    delegate_->OnAvatarErrorChanged();
+  // Always notify observers, so they can handle errors differently.
+  delegate_->OnAvatarErrorChanged();
 }
 
 AvatarButtonErrorController::SigninErrorObserver::SigninErrorObserver(