Moved a lock creation to CreateEventThread.

It is more symetric with StopEventThread.

modules/video_output/msw/direct3d.c

@@ -197,7 +197,6 @@ static int OpenVideo( vlc_object_t *p_this )
     p_vout->p_sys->hparent = p_vout->p_sys->hfswnd = NULL;
     p_vout->p_sys->i_changes = 0;
     p_vout->p_sys->b_desktop = false;
-    vlc_mutex_init( &p_vout->p_sys->lock );
     SetRectEmpty( &p_vout->p_sys->rect_display );
     SetRectEmpty( &p_vout->p_sys->rect_parent );
 

modules/video_output/msw/directx.c

@@ -234,7 +234,6 @@ static int OpenVideo( vlc_object_t *p_this )
     p_vout->p_sys->hparent = p_vout->p_sys->hfswnd = NULL;
     p_vout->p_sys->i_changes = 0;
     p_vout->p_sys->b_wallpaper = 0;
-    vlc_mutex_init( &p_vout->p_sys->lock );
     SetRectEmpty( &p_vout->p_sys->rect_display );
     SetRectEmpty( &p_vout->p_sys->rect_parent );
 

modules/video_output/msw/events.c

@@ -1334,6 +1334,9 @@ void RestoreScreensaver( vout_thread_t *p_vout )
 
 int CreateEventThread( vout_thread_t *p_vout )
 {
+    if( !( p_vout->p_sys->i_changes & SWITCHING_MODE_FLAG ) )
+        vlc_mutex_init( &p_vout->p_sys->lock );
+
     /* Create the Vout EventThread, this thread is created by us to isolate
      * the Win32 PeekMessage function calls. We want to do this because
      * Windows can stay blocked inside this call for a long time, and when

modules/video_output/msw/glwin32.c

@@ -106,7 +106,6 @@ static int OpenVideo( vlc_object_t *p_this )
     p_vout->p_sys->hwnd = p_vout->p_sys->hvideownd = NULL;
     p_vout->p_sys->hparent = p_vout->p_sys->hfswnd = NULL;
     p_vout->p_sys->i_changes = 0;
-    vlc_mutex_init( &p_vout->p_sys->lock );
     SetRectEmpty( &p_vout->p_sys->rect_display );
     SetRectEmpty( &p_vout->p_sys->rect_parent );
 

modules/video_output/msw/wingdi.c

@@ -165,7 +165,6 @@ static int OpenVideo ( vlc_object_t *p_this )
     p_vout->p_sys->hwnd = p_vout->p_sys->hvideownd = NULL;
     p_vout->p_sys->hparent = p_vout->p_sys->hfswnd = NULL;
     p_vout->p_sys->i_changes = 0;
-    vlc_mutex_init( &p_vout->p_sys->lock );
     SetRectEmpty( &p_vout->p_sys->rect_display );
     SetRectEmpty( &p_vout->p_sys->rect_parent );