Web Inspector: Timelines Tab: Screenshots: show placeholder text when…

… there's no images

https://bugs.webkit.org/show_bug.cgi?id=240851

Reviewed by Patrick Angle.

* Source/WebInspectorUI/UserInterface/Views/ScreenshotsTimelineView.js:
(WI.ScreenshotsTimelineView.prototype.layout):

* Source/WebInspectorUI/Localizations/en.lproj/localizedStrings.js:

Canonical link: https://commits.webkit.org/250927@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@294759 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebInspectorUI/Localizations/en.lproj/localizedStrings.js

@@ -1029,6 +1029,8 @@ localizedStrings["No request, served from the disk cache."] = "No request, serve
 localizedStrings["No request, served from the memory cache."] = "No request, served from the memory cache.";
 localizedStrings["No response cookies."] = "No response cookies.";
 localizedStrings["No response headers"] = "No response headers";
+/* Placeholder text shown when there are no images to display in the Screenshots timeline. */
+localizedStrings["No screenshots @ Screenshots Timeline"] = "No screenshots";
 localizedStrings["No search results"] = "No search results";
 localizedStrings["No search string"] = "No search string";
 localizedStrings["Node"] = "Node";

Source/WebInspectorUI/UserInterface/Views/ScreenshotsTimelineView.js

@@ -79,6 +79,9 @@ WI.ScreenshotsTimelineView = class ScreenshotsTimelineView extends WI.TimelineVi
                 this._selectTimelineRecord(record);
             });
         }        
+
+        if (!this.element.childNodes.length)
+            this.element.appendChild(WI.createMessageTextView(WI.UIString("No screenshots", "No screenshots @ Screenshots Timeline", "Placeholder text shown when there are no images to display in the Screenshots timeline.")));
     }
 
     selectRecord(record)