Convert almost all IdleRegister::add() calls to add(std::function<>)

rtgui/retinex.cc

@@ -672,28 +672,20 @@ void Retinex::minmaxChanged (double cdma, double cdmin, double mini, double maxi
     nextminT = Tmin;
     nextmaxT = Tmax;
 
-    const auto func =
-        [](Retinex* self) -> bool
+    idle_register.add(
+        [this]() -> bool
         {
             GThreadLock lock; // All GUI access from idle_add callbacks or separate thread HAVE to be protected
             // FIXME: The above can't be true?!
-            self->minmaxComputed_();
+            disableListener();
+            enableListener();
+            updateLabel();
+            updateTrans();
             return false;
-        };
-
-    idle_register.add<Retinex>(func, this, false);
+        }
+    );
 }
 
-bool Retinex::minmaxComputed_ ()
-{
-
-    disableListener ();
-    enableListener ();
-    updateLabel ();
-    updateTrans ();
-    return false;
-
-}
 void Retinex::updateLabel ()
 {
     if (!batchMode) {