provide GetSize() getters in wxBitmap and wxImage

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@57014 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/bitmap.h

@@ -440,6 +440,8 @@ public:
 
     /**
         Gets the height of the bitmap in pixels.
+
+        @see GetWidth(), GetSize()
     */
     virtual int GetHeight() const;
 
@@ -465,10 +467,19 @@ public:
     */
     virtual wxBitmap GetSubBitmap(const wxRect& rect) const;
 
+    /**
+        Returns the size of the bitmap in pixels.
+
+        @since 2.9.0
+
+        @see GetHeight(), GetWidth()
+    */
+    wxSize GetSize() const;
+
     /**
         Gets the width of the bitmap in pixels.
 
-        @see GetHeight()
+        @see GetHeight(), GetSize()
     */
     virtual int GetWidth() const;