Don't overwrite window mode settings when switching between WM and non-WM environments

app/streaming/session.h

@@ -133,6 +133,7 @@ private:
     int drSubmitDecodeUnit(PDECODE_UNIT du);
 
     StreamingPreferences* m_Preferences;
+    bool m_IsFullScreen;
     STREAM_CONFIGURATION m_StreamConfig;
     DECODER_RENDERER_CALLBACKS m_VideoCallbacks;
     AUDIO_RENDERER_CALLBACKS m_AudioCallbacks;