winex11.drv: Send HTMENU instead of HTCAPTION to query window activat…

…ion.

Commit 71d35d8 broke the way
WM_TAKE_FOCUS protocol is implemented: WM_MOUSEACTIVATE now replies
MA_NOACTIVATE by default when using HTCAPTION.

We use the WM_MOUSEACTIVATE -although Windows does not- regardless of
the way focus is changed to check whether a window wants focus, and
Windows sometimes changes focus regardless of the message reply.

Steam and the Wine system tray are affected for instance.

Signed-off-by: Rémi Bernon <rbernon@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>

dlls/winex11.drv/event.c

@@ -706,7 +706,7 @@ static void handle_wm_protocols( HWND hwnd, XClientMessageEvent *event )
              * whether the window wants to be activated */
             LRESULT ma = SendMessageW( hwnd, WM_MOUSEACTIVATE,
                                        (WPARAM)GetAncestor( hwnd, GA_ROOT ),
-                                       MAKELONG(HTCAPTION,WM_LBUTTONDOWN) );
+                                       MAKELONG( HTMENU, WM_LBUTTONDOWN ) );
             if (ma != MA_NOACTIVATEANDEAT && ma != MA_NOACTIVATE)
             {
                 set_focus( event->display, hwnd, event_time );