Manage readonly state on boolean in Dict widget

issue7341
review42081002

src/view/form.js

@@ -4288,6 +4288,10 @@ function eval_pyson(value){
         get_value: function() {
             return this.input.prop('checked');
         },
+        set_readonly: function(readonly) {
+            this._readonly = readonly;
+            this.input.prop('disabled', readonly);
+        },
         set_value: function(value) {
             this.input.prop('checked', value);
         }