If zero time is specified, don't try to sleep when using a timer.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_4_BRANCH@19545 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/utils.cpp

@@ -1104,6 +1104,8 @@ void wxUsleep(unsigned long milliseconds)
 #else // !Win32
     if (gs_inTimer)
         return;
+    if (miliseconds <= 0)
+        return;
 
     wxTheSleepTimer = new wxSleepTimer;
     gs_inTimer = TRUE;
@@ -1122,6 +1124,8 @@ void wxSleep(int nSecs)
 {
     if (gs_inTimer)
         return;
+    if (nSecs <= 0)
+        return;
 
     wxTheSleepTimer = new wxSleepTimer;
     gs_inTimer = TRUE;