Fix paint VolumeBar on InfoViewer

Origin commit data
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Commit: 31e2dae622
Author: Michael Liebmann <tuxcode.bbg@gmail.com>
Date: 2013-06-26 (Wed, 26 Jun 2013)

src/driver/volume.h

@@ -51,6 +51,8 @@ class CVolume : public CChangeObserver
 
 		void SetCurrentPid(int pid) { apid = pid; }
 		void SetCurrentChannel(t_channel_id id) { channel_id = id; }
+		bool hideVolscale();
+		void showVolscale();
 		bool changeNotify(const neutrino_locale_t OptionName, void *);
 };