Remove trailing whitespace from several files

No real changes.

See https://github.com/wxWidgets/wxWidgets/pull/787

src/common/ctrlcmn.cpp

@@ -275,7 +275,7 @@ struct EllipsizeCalculator
 {
     EllipsizeCalculator(const wxString& s, const wxDC& dc,
                         int maxFinalWidthPx, int replacementWidthPx)
-        : 
+        :
           m_initialCharToRemove(0),
           m_nCharsToRemove(0),
           m_outputNeedsUpdate(true),
@@ -522,7 +522,7 @@ wxString wxControlBase::Ellipsize(const wxString& label, const wxDC& dc,
 {
     if (mode == wxELLIPSIZE_NONE)
         return label;
-    
+
     wxString ret;
 
     // these cannot be cached between different Ellipsize() calls as they can