Added message about synthesize keyword.

Jaime O. Rios · Jaime O. Rios · commit 10651d491f66 · 2017-03-03T09:43:44.000-05:00
diff --git a/modules/highgui/src/window_cocoa.mm b/modules/highgui/src/window_cocoa.mm
@@ -1001,6 +1001,7 @@ @implementation CVSlider
 @synthesize callback;
 @synthesize callback2;
 #else
+// 32-bit Obj-C does not have automatic synthesize
 @synthesize slider = _slider;
 @synthesize name = _name;
 @synthesize value = _value;
