Discard stale gamepad events when enabling gamepad navigation

app/gui/sdlgamepadkeynavigation.cpp

@@ -12,6 +12,7 @@
 SdlGamepadKeyNavigation::SdlGamepadKeyNavigation()
     : m_Enabled(false),
       m_UiNavMode(false),
+      m_FirstPoll(false),
       m_LastAxisNavigationEventTime(0)
 {
     m_PollingTimer = new QTimer(this);
@@ -62,6 +63,9 @@ void SdlGamepadKeyNavigation::enable()
         }
     }
 
+    // Flush events on the first poll
+    m_FirstPoll = true;
+
     // Poll every 50 ms for a new joystick event
     m_PollingTimer->start(50);
 
@@ -91,6 +95,16 @@ void SdlGamepadKeyNavigation::onPollingTimerFired()
     SDL_Event event;
     StreamingPreferences prefs;
 
+    // Discard any pending button events on the first poll to avoid picking up
+    // stale input data from the stream session (like the quit combo).
+    if (m_FirstPoll) {
+        SDL_PumpEvents();
+        SDL_FlushEvent(SDL_CONTROLLERBUTTONDOWN);
+        SDL_FlushEvent(SDL_CONTROLLERBUTTONUP);
+
+        m_FirstPoll = false;
+    }
+
     while (SDL_PollEvent(&event)) {
         switch (event.type) {
         case SDL_QUIT:

app/gui/sdlgamepadkeynavigation.h

@@ -34,5 +34,6 @@ private:
     QList<SDL_GameController*> m_Gamepads;
     bool m_Enabled;
     bool m_UiNavMode;
+    bool m_FirstPoll;
     Uint32 m_LastAxisNavigationEventTime;
 };