Fix text cropping when using ellipsization in wxGrid

A text is cropped for cells with ellipsization enabled when width of the
cell nearly equal to width of the text because wxGrid::DrawTextRectangle
function variant with the parameter of type wxArrayString adds the offset
before actually drawing the text using dc.DrawText or dc.DrawRotatedText.

src/generic/grid.cpp

@@ -6831,13 +6831,16 @@ void wxGrid::DrawTextRectangle(wxDC& dc,
 {
     attr.GetNonDefaultAlignment(&hAlign, &vAlign);
 
+    // The text will be displaced in final wxGrid::DrawTextRectangle function.
+    const int textMargin = 2;
+
     // This does nothing if there is no need to ellipsize.
     const wxString& ellipsizedText = wxControl::Ellipsize
                                      (
                                          text,
                                          dc,
                                          attr.GetFitMode().GetEllipsizeMode(),
-                                         rect.GetWidth(),
+                                         rect.GetWidth() - textMargin,
                                          wxELLIPSIZE_FLAGS_NONE
                                      );