Make render sample window bigger initially

It wasn't big enough to show all of its contents.

samples/render/render.cpp

@@ -424,9 +424,7 @@ bool MyApp::OnInit()
 MyFrame::MyFrame()
        : wxFrame(NULL,
                  wxID_ANY,
-                 wxT("Render wxWidgets Sample"),
-                 wxPoint(50, 50),
-                 wxSize(450, 340))
+                 wxT("Render wxWidgets Sample"))
 {
     // set the frame icon
     SetIcon(wxICON(sample));
@@ -481,6 +479,8 @@ MyFrame::MyFrame()
 
     m_panel = new MyPanel(this);
 
+    SetClientSize(600, 600);
+
 #if wxUSE_STATUSBAR
     // create a status bar just for fun (by default with 1 pane only)
     CreateStatusBar(2);