Layout Track / Via Properties dialog.

It's sizing is dependent on the selection.

Fixes: lp:1772260
* https://bugs.launchpad.net/kicad/+bug/1772260

pcbnew/dialogs/dialog_track_via_properties.cpp

@@ -321,6 +321,8 @@ DIALOG_TRACK_VIA_PROPERTIES::DIALOG_TRACK_VIA_PROPERTIES( PCB_BASE_FRAME* aParen
 
     m_StdButtonsOK->SetDefault();
 
+    Layout();
+    
     // Pressing ENTER when any of the text input fields is active applies changes
     Connect( wxEVT_TEXT_ENTER, wxCommandEventHandler( DIALOG_TRACK_VIA_PROPERTIES::onOkClick ),
              NULL, this );