Applying patch #10784: eliminate gauge flicker

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62069 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/gauge.cpp

@@ -206,6 +206,10 @@ void wxGauge::SetRange(int r)
 
 void wxGauge::SetValue(int pos)
 {
+    // Setting the (same) position produces flicker on Vista,
+    // especially noticable if ownerdrawn
+    if (GetValue() == pos) return;
+
     // switch to determinate mode if required
     SetDeterminateMode();