JS - Add support for display property

- in annotation_layer, move common properties treatment in a common method instead having duplicated code in each widget.

src/scripting_api/proxy.js

@@ -14,6 +14,13 @@
  */
 
 class ProxyHandler {
+  constructor() {
+    // Don't dispatch an event for those properties.
+    //  - delay: allow to delay field redraw until delay is set to false.
+    //    Likely it's useless to implement that stuff.
+    this.nosend = new Set(["delay"]);
+  }
+
   get(obj, prop) {
     // script may add some properties to the object
     if (prop in obj._expandos) {
@@ -49,7 +56,12 @@ class ProxyHandler {
     if (typeof prop === "string" && !prop.startsWith("_") && prop in obj) {
       const old = obj[prop];
       obj[prop] = value;
-      if (obj._send && obj._id !== null && typeof old !== "function") {
+      if (
+        !this.nosend.has(prop) &&
+        obj._send &&
+        obj._id !== null &&
+        typeof old !== "function"
+      ) {
         const data = { id: obj._id };
         data[prop] = obj[prop];