VPN-2934 - Fix device limit issues when logging out manually from oth…

…er device (#4623)

* Start periodic operations timer whenver a token is available

1. That is all we need to run those operations
2. That ensures the operations are run also when in the device limit
   screen.

* Skip device check when in StateDeviceLimit

* Always enqueue a remove device task regardless if device is in
DeviceModel

TaskRemoveDevice already deals with the possibility of the device
not being registered to the given user. No need to handle
that in multiple places.

Also by not launching task remove device, operations to take
user out of device limit state don't happen and that leaves users
trapped in device limit screen.

src/mozillavpn.cpp

@@ -352,13 +352,18 @@ void MozillaVPN::setState(State state) {
   emit MozillaVPN::instance()->recordGleanEventWithExtraKeys(
       GleanSample::appStep, {{"state", QVariant::fromValue(state).toString()}});
 
-  // If we are activating the app, let's initialize the controller.
-  if (m_state == StateMain) {
-    m_private->m_controller.initialize();
+  // If we have a token, we can start periodic operations.
+  // If the timer is already started, this is a no-op.
+  if (SettingsHolder::instance()->hasToken()) {
     startSchedulingPeriodicOperations();
   } else {
     stopSchedulingPeriodicOperations();
   }
+
+  // If we are activating the app, let's initialize the controller.
+  if (m_state == StateMain) {
+    m_private->m_controller.initialize();
+  }
 }
 
 void MozillaVPN::maybeStateMain() {
@@ -682,12 +687,6 @@ void MozillaVPN::deviceRemovalCompleted(const QString& publicKey) {
 void MozillaVPN::removeDeviceFromPublicKey(const QString& publicKey) {
   logger.debug() << "Remove device";
 
-  const Device* device =
-      m_private->m_deviceModel.deviceFromPublicKey(publicKey);
-  if (!device) {
-    return;
-  }
-
   // Let's emit a signal to inform the user about the starting of the device
   // removal.  The front-end code will show a loading icon or something
   // similar.
@@ -810,6 +809,11 @@ bool MozillaVPN::checkCurrentDevice() {
   SettingsHolder* settingsHolder = SettingsHolder::instance();
   Q_ASSERT(settingsHolder);
 
+  // We are not able to check the device at this stage.
+  if (m_state == StateDeviceLimit) {
+    return false;
+  }
+
   if (m_private->m_deviceModel.hasCurrentDevice(keys())) {
     return true;
   }