CTextBox: ensure paint of background to avoid overlapped letters

Origin commit data
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Commit: 08e23a917c
Author: Thilo Graf <dbt@novatux.de>
Date: 2013-09-16 (Mon, 16 Sep 2013)

src/gui/widget/textbox.h

@@ -150,6 +150,7 @@ class CTextBox
 		int m_nFontTextHeight;
 		CFBWindow::color_t m_textBackgroundColor;
 		fb_pixel_t m_textColor;
+		fb_pixel_t* m_bgpixbuf;
 
 		CFrameBuffer * frameBuffer;
 /*		int max_width;*/