Moved Clear() implementation into wxDC using a new virtual CocoaGetBounds()

to determine the rect to clear.  Also added CocoaUnapplyTransformations()
to bring the coordinate system back into Cocoa coordinates for those
cases such as Clear() where it makes more sense.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@31440 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/cocoa/dcmemory.h

@@ -23,14 +23,13 @@ public:
     ~wxMemoryDC(void);
     virtual void SelectObject(const wxBitmap& bitmap);
     virtual void DoGetSize(int *width, int *height) const;
-
-    virtual void Clear();
 protected:
     wxBitmap m_selectedBitmap;
     WX_NSImage m_cocoaNSImage;
 // DC stack
     virtual bool CocoaLockFocus();
     virtual bool CocoaUnlockFocus();
+    virtual bool CocoaGetBounds(void *rectData);
 // Blitting
     virtual bool CocoaDoBlitOnFocusedDC(wxCoord xdest, wxCoord ydest,
         wxCoord width, wxCoord height, wxCoord xsrc, wxCoord ysrc,