Improved management of online status from non-primary windows.

– The online status of the user should be checked and updated only
when the previous active window and the current active window both have
different sessions.
– Removed MainWindow::activeChangedHook since windows should not
change online status on their own on activating.
– Renamed Application::maybeActiveSession
to Application::maybePrimarySession.
– Added updating of online status on changing of the current account
since this seems to have been missed.

Telegram/SourceFiles/mainwindow.cpp

@@ -718,12 +718,6 @@ void MainWindow::sendPaths() {
 	}
 }
 
-void MainWindow::activeChangedHook() {
-	if (const auto controller = sessionController()) {
-		controller->session().updates().updateOnline();
-	}
-}
-
 MainWindow::~MainWindow() = default;
 
 namespace App {