Undid accidental modification of wxTaskBarIcon in the last commit.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72437 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/taskbar.cpp

@@ -110,8 +110,10 @@ static BOOL wxShellNotifyIcon(DWORD dwMessage, NOTIFYICONDATA *pData)
 // wxTaskBarIconWindow: helper window
 // ----------------------------------------------------------------------------
 
-// We need a HWND to create a taskbar icon, so create a special hidden window
-// just to be able to use its HWND.
+// NB: this class serves two purposes:
+//     1. win32 needs a HWND associated with taskbar icon, this provides it
+//     2. we need wxTopLevelWindow so that the app doesn't exit when
+//        last frame is closed but there still is a taskbar icon
 class wxTaskBarIconWindow : public wxFrame
 {
 public:
@@ -121,11 +123,6 @@ public:
     {
     }
 
-    // This implicitly created window shouldn't prevent the application from
-    // exiting if all its other windows are closed.
-    virtual bool ShouldPreventAppExit() const { return false; }
-
-protected:
     WXLRESULT MSWWindowProc(WXUINT msg,
                             WXWPARAM wParam, WXLPARAM lParam)
     {