gui/osd_helpers.cpp/h: add signal OnAfterChangeResolution

Adds possibility to use any methods after changed resolution without
any changes on COsdHelpers class.
Implementation is possible directly from other objects that need this.


Origin commit data
------------------
Branch: ni/coolstream
Commit: cfdd351ceb
Author: Thilo Graf <dbt@novatux.de>
Date: 2019-04-07 (Sun, 07 Apr 2019)



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This commit was generated by Migit

src/gui/osd_helpers.cpp

@@ -123,6 +123,7 @@ void COsdHelpers::changeOsdResolution(uint32_t mode, bool automode/*=false*/, bo
 			CNeutrinoApp::getInstance()->StartSubtitles();
 		}
 	}
+	OnAfterChangeResolution();
 }
 #else
 void COsdHelpers::changeOsdResolution(uint32_t, bool, bool)

src/gui/osd_helpers.h

@@ -2,12 +2,14 @@
 #ifndef __osd_helpers__
 #define __osd_helpers__
 
+#include <sigc++/signal.h>
+
 enum {
 	OSDMODE_720  = 0,
 	OSDMODE_1080 = 1
 };
 
-class COsdHelpers
+class COsdHelpers : public sigc::trackable
 {
 	private:
 
@@ -23,6 +25,7 @@ class COsdHelpers
 		int  getVideoSystem();
 		uint32_t getOsdResolution();
 		int setVideoSystem(int newSystem, bool remember = true);
+		sigc::signal<void> OnAfterChangeResolution;
 };