Fix modal live preview not updating

Due to the behavior of scheduleAfterUiUpdateCallbacks if opts.live_preview_refresh_period < 200ms live preview in Modal image viewer may not update
Assing updateModalImageIfVisible as alias for updateOnBackgroundChange as the origin name is too generic

Author: w-e-w

.eslintrc.js

@@ -88,6 +88,7 @@ module.exports = {
         // imageviewer.js
         modalPrevImage: "readonly",
         modalNextImage: "readonly",
+        updateModalImageIfVisible: "readonly",
         // localStorage.js
         localSet: "readonly",
         localGet: "readonly",

javascript/imageviewer.js

@@ -54,6 +54,7 @@ function updateOnBackgroundChange() {
         updateModalImage();
     }
 }
+const updateModalImageIfVisible = updateOnBackgroundChange;
 
 function modalImageSwitch(offset) {
     var galleryButtons = all_gallery_buttons();

javascript/progressbar.js

@@ -190,7 +190,7 @@ function requestProgress(id_task, progressbarContainer, gallery, atEnd, onProgre
                         livePreview.className = 'livePreview';
                         gallery.insertBefore(livePreview, gallery.firstElementChild);
                     }
-
+                    updateModalImageIfVisible();
                     livePreview.appendChild(img);
                     if (livePreview.childElementCount > 2) {
                         livePreview.removeChild(livePreview.firstElementChild);