winex11: Restore the X11DRV_FLUSH_GL_DRAWABLE XFlush() for setups without OML_sync_control.

dlls/winex11.drv/init.c

@@ -259,6 +259,7 @@ static INT X11DRV_ExtEscape( PHYSDEV dev, INT escape, INT in_count, LPCVOID in_d
                     RECT rect = physDev->dc_rect;
 
                     OffsetRect( &rect, -physDev->dc_rect.left, -physDev->dc_rect.top );
+                    if (data->flush) XFlush( gdi_display );
                     XSetFunction( gdi_display, physDev->gc, GXcopy );
                     XCopyArea( gdi_display, data->gl_drawable, physDev->drawable, physDev->gc,
                                0, 0, rect.right, rect.bottom,

dlls/winex11.drv/opengl.c

@@ -1976,6 +1976,7 @@ static void wglFinish(void)
 
     escape.code = X11DRV_FLUSH_GL_DRAWABLE;
     escape.gl_drawable = 0;
+    escape.flush = FALSE;
 
     if ((gl = get_gl_drawable( WindowFromDC( ctx->hdc ), 0 )))
     {
@@ -2001,6 +2002,7 @@ static void wglFlush(void)
 
     escape.code = X11DRV_FLUSH_GL_DRAWABLE;
     escape.gl_drawable = 0;
+    escape.flush = FALSE;
 
     if ((gl = get_gl_drawable( WindowFromDC( ctx->hdc ), 0 )))
     {
@@ -3286,6 +3288,7 @@ static BOOL glxdrv_wglSwapBuffers( HDC hdc )
 
     escape.code = X11DRV_FLUSH_GL_DRAWABLE;
     escape.gl_drawable = 0;
+    escape.flush = !pglXWaitForSbcOML;
 
     if (!(gl = get_gl_drawable( WindowFromDC( hdc ), hdc )))
     {

dlls/winex11.drv/x11drv.h

@@ -304,6 +304,7 @@ struct x11drv_escape_flush_gl_drawable
 {
     enum x11drv_escape_codes code;         /* escape code (X11DRV_FLUSH_GL_DRAWABLE) */
     Drawable                 gl_drawable;  /* GL drawable */
+    BOOL                     flush;        /* flush X11 before copying */
 };
 
 /**************************************************************************