[OS/2] Bug 506997: optimize repainting after window moves, r=dragtext

widget/src/os2/nsWindow.cpp

@@ -103,9 +103,6 @@ static const char *sScreenManagerContractID = "@mozilla.org/gfx/screenmanager;1"
 // NS2PM methods for conversion of points & rectangles; position is a bit
 // different in that it's the *parent* window whose height must be used.
 //
-// Deferred window positioning is emulated using WinSetMultWindowPos in
-// the hopes that there was a good reason for adding it to nsIWidget.
-//
 // SetColorSpace() is not implemented on purpose.  So there.
 //
 // John Fairhurst 17-09-98 first version
@@ -1354,9 +1351,12 @@ NS_METHOD nsWindow::Resize(PRInt32 aX,
          ptl.y = WinQuerySysValue(HWND_DESKTOP, SV_CYSCREEN) - h - 1 - aY;
       }
 
-      WinSetWindowPos(GetMainWindow(), 0, ptl.x, ptl.y, w, h, SWP_MOVE | SWP_SIZE);
-      if (aRepaint)
-         Invalidate(PR_FALSE);
+      if (!WinSetWindowPos(GetMainWindow(), 0, ptl.x, ptl.y, w, h,
+                           SWP_MOVE | SWP_SIZE)) {
+         if (aRepaint) {
+            Invalidate(PR_FALSE);
+         }
+      }
 
 #if DEBUG_sobotka
       printf("+++++++++++Resized 0x%lx at %ld, %ld to %d x %d (%d,%d)\n",