[0.4.13] Anti-flicker backport winpos.c

This effective one-liner-backport fixes flickering in some apps like:
- CORE-7652 Hyperlink Blinking text while installing vc2008 redist package
and many duplicate-tickets of that same symptom, like:
- CORE-18553 CPUID CPU-Z 1.84 "about" flickers
- CORE-7753 Caesar 3: Autorun.exe flickers endlessly
- CORE-10741 API monitor high CPU usage
- CORE-15300 Worksoft Navigator 0.985 installer is locked in an endless redrawing loop
- CORE-16325 Some of MWSnap's installation windows fail to display content
- CORE-17925 MS Visual C++ 2008 Redistributable Setup takes long time
- CORE-18153 BitComet 1.86 forces the shell to a endless redrawing
- CORE-18434 Ubisoft installers (SetupUbi) - continously refresh of window
- CORE-15546 Shed 1.0 from rapps - setup does not draw some dlgs initially, but redraw can be enforced
- CORE-18582 Emule 0.50a - Interface frozen / flickering until window is moved

And since I do also port back the follow-up-commit of that, we can achieve that without introducing
the following regressions which the initial fixes caused:
- CORE-18817 [NTUSER] Winpos.c modification generates bad first drawing of some elements
- CORE-18830 Explorer Drawing glitch: Missing "X" on "Folder" pane when Right Click > Explore from Desktop icons
Those 2 things did not happen in the older releases beforehand.

In sum this is a squashed backport of:
0.4.15-dev-6507-g 49dbc8fbbb [NTUSER] Whitespace-fixes winpos.c
0.4.15-dev-5684-g 57eb2a6bf4 [NTUSER] Missing "X" on "Folder" pane when Right Click > Explore from Desktop icons & Rapps toolbar errors (#5068) CORE-18830, CORE-18817
the superseded 0.4.15-dev-5618-g 8866b9d7b0 Update win32ss/user/ntuser/winpos.c
the superseded 0.4.15-dev-5617-g 7866eb2886 [NTUSER] Fix winpos bug hyperlink&images loop redrawing CORE-7652 (#4995)

To prevent increased binary size for the added conditions in the code in older branches, strip a single good-path-TRACE()
which had no trailing \n in the older branches,
but where that \n was added in master head meanwhile. So that TRACE was a diff to older branches anyway.

win32ss/user/ntuser/winpos.c

@@ -1,9 +1,8 @@
 /*
- * COPYRIGHT:        See COPYING in the top level directory
- * PROJECT:          ReactOS kernel
- * PURPOSE:          Windows
- * FILE:             win32ss/user/ntuser/winpos.c
- * PROGRAMER:        Casper S. Hornstrup (chorns@users.sourceforge.net)
+ * COPYRIGHT:   See COPYING in the top level directory
+ * PROJECT:     ReactOS kernel
+ * PURPOSE:     Windows
+ * PROGRAMER:   Casper S. Hornstrup (chorns@users.sourceforge.net)
  */
 
 #include <win32k.h>
@@ -437,7 +436,7 @@ co_WinPosActivateOtherWindow(PWND Wnd)
    // Find any window to bring to top. Works Okay for wine since it does not see X11 windows.
    WndTo = UserGetDesktopWindow();
    WndTo = WndTo->spwndChild;
-   if ( WndTo == NULL )
+   if (WndTo == NULL)
    {
       //ERR("WinPosActivateOtherWindow No window!\n");
       return;
@@ -1747,8 +1746,6 @@ co_WinPosSetWindowPos(
 
    ASSERT_REFS_CO(Window);
 
-   TRACE("pwnd %p, after %p, %d,%d (%dx%d), flags 0x%x",
-          Window, WndInsertAfter, x, y, cx, cy, flags);
 #if DBG
    dump_winpos_flags(flags);
 #endif
@@ -1948,7 +1945,7 @@ co_WinPosSetWindowPos(
       Window->state |= WNDS_SENDNCPAINT;
    }
 
-   if (!(WinPos.flags & SWP_NOREDRAW))
+   if (!(WinPos.flags & SWP_NOREDRAW) && ((WinPos.flags & SWP_AGG_STATUSFLAGS) != SWP_AGG_NOPOSCHANGE))
    {
       /* Determine the new visible region */
       VisAfter = VIS_ComputeVisibleRegion(Window, FALSE, FALSE,
@@ -2105,7 +2102,7 @@ co_WinPosSetWindowPos(
                 }
                 IntInvalidateWindows(Window, DirtyRgn, RDW_ERASE | RDW_FRAME | RDW_INVALIDATE | RDW_ALLCHILDREN);
              }
-             else if ( RgnType != ERROR && RgnType == NULLREGION ) // Must be the same. See CORE-7166 & CORE-15934, NC HACK fix.
+             else if (RgnType != ERROR && RgnType == NULLREGION) // Must be the same. See CORE-7166 & CORE-15934, NC HACK fix.
              {
                 if ( !PosChanged &&
                      !(WinPos.flags & SWP_DEFERERASE) &&
@@ -2154,7 +2151,7 @@ co_WinPosSetWindowPos(
       }
 
       /* Expose what was covered before but not covered anymore */
-      if ( VisBefore != NULL )
+      if (VisBefore != NULL)
       {
          PREGION ExposedRgn = IntSysCreateRectpRgn(0, 0, 0, 0);
          if (ExposedRgn)
@@ -2164,7 +2161,7 @@ co_WinPosSetWindowPos(
                                OldWindowRect.left - NewWindowRect.left,
                                OldWindowRect.top  - NewWindowRect.top);
 
-             if ( VisAfter != NULL )
+             if (VisAfter != NULL)
                 RgnType = IntGdiCombineRgn(ExposedRgn, ExposedRgn, VisAfter, RGN_DIFF);
 
              if (RgnType != ERROR && RgnType != NULLREGION)
@@ -2212,7 +2209,7 @@ co_WinPosSetWindowPos(
        if ( !(Window->style & WS_CHILD) && (Parent) && (Parent->style & WS_CLIPCHILDREN))
        {
            TRACE("SWP_FRAMECHANGED Parent %p WS_CLIPCHILDREN %p\n",Parent,Window);
-           UserSyncAndPaintWindows( Parent, RDW_CLIPCHILDREN); // NC should redraw here, see NC HACK fix.
+           UserSyncAndPaintWindows(Parent, RDW_CLIPCHILDREN); // NC should redraw here, see NC HACK fix.
        }
    }
 
@@ -3068,7 +3065,7 @@ END:
     return retvalue;
 }
 
-BOOL FASTCALL IntEndDeferWindowPosEx( HDWP hdwp, BOOL sAsync )
+BOOL FASTCALL IntEndDeferWindowPosEx(HDWP hdwp, BOOL sAsync)
 {
     PSMWP pDWP;
     PCVR winpos;
@@ -3098,7 +3095,7 @@ BOOL FASTCALL IntEndDeferWindowPosEx( HDWP hdwp, BOOL sAsync )
 
         UserRefObjectCo(pwnd, &Ref);
 
-        if ( sAsync )
+        if (sAsync)
         {
            LRESULT lRes;
            PWINDOWPOS ppos = ExAllocatePoolWithTag(PagedPool, sizeof(WINDOWPOS), USERTAG_SWP);