simplifications and corrections to background drawing:

1. removed ApplyParentThemeBackground() not used any longer
2. removed ProvidesBackground() which is synonymous with
   !HasTransparentBackground()
3. removed a whole bunch of unused MSWXXX() methods
4. moved MSWControlColor() from wxWindow up to wxControl

results:

1. the gradient is still shown properly for static/radio boxes in notebooks
2. correct background colour is used for the static boxes
3. code is shorter and better commented


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@33474 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/private.h

@@ -722,6 +722,14 @@ extern WXDLLEXPORT wxSize wxGetHiconSize(HICON hicon);
 // Lines are drawn differently for WinCE and regular WIN32
 WXDLLEXPORT void wxDrawLine(HDC hdc, int x1, int y1, int x2, int y2);
 
+// fill the client rect of the given window on the provided dc using this brush
+inline void wxFillRect(HWND hwnd, HDC hdc, HBRUSH hbr)
+{
+    RECT rc;
+    ::GetClientRect(hwnd, &rc);
+    ::FillRect(hdc, &rc, hbr);
+}
+
 // ----------------------------------------------------------------------------
 // 32/64 bit helpers
 // ----------------------------------------------------------------------------