wxwidgets: Hide dumper called "NULL"

This is not working dumper (it is meant for PGO using lsnes-dumpavi),
so don't show it.

include/core/advdumper.hpp

@@ -105,6 +105,10 @@ public:
  */
 	virtual dumper_base* start(master_dumper& _mdumper, const std::string& mode, const std::string& targetname)
 		throw(std::bad_alloc, std::runtime_error) = 0;
+/**
+ * Is hidden?
+ */
+	virtual bool hidden() const { return false; }
 /**
  * Add dumper update notifier object.
  */

include/core/ui-services.hpp

@@ -49,6 +49,8 @@ struct dumper_information_1
 	std::string name;
 	//Is this dumper active?
 	bool active;
+	//Hidden?
+	bool hidden;
 	//Modes available (first is internal name, second is human-readable one).
 	std::map<std::string, std::string> modes;
 };

src/core/ui-services.cpp

@@ -32,6 +32,7 @@ namespace
 		for(auto i : mset)
 			inf.modes[i] = d->modename(i);
 		inf.active = inst.mdumper->busy(d);
+		inf.hidden = d->hidden();
 		new_dumpers[d->id()] = inf;
 	}
 }

src/platform/wxwidgets/dumpmenu.cpp

@@ -164,6 +164,9 @@ void dumper_menu::update()
 	first = true;
 	menustructure.clear();
 	for(auto i : dinfo.dumpers) {
+		//Skip dumper called "NULL" unless actually active, since it doesn't really work.
+		if(i.second.hidden && !i.second.active)
+			continue;
 		if(!first)
 			menustructure[last_processed].sep = AppendSeparator();
 		last_processed = i.first;

src/video/null.cpp

@@ -103,6 +103,7 @@ namespace
 		{
 			return new null_dump_obj(_mdumper, *this, mode, prefix);
 		}
+		bool hidden() const { return true; }
 	} adv;
 
 	adv_null_dumper::~adv_null_dumper() throw()