[CQ] de-duplicate panel label replacement logic (#8232)

Opportunistic de-duplication.

---

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portions to this PR.

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Author: pq

flutter-idea/src/io/flutter/view/EmbeddedBrowser.java

@@ -207,17 +207,7 @@ protected void showLabels(List<LabelInput> labels, ContentManager contentManager
   }
 
   private void replacePanelLabel(JComponent label, ContentManager contentManager) {
-    OpenApiUtils.safeInvokeLater(() -> {
-      if (contentManager.isDisposed()) {
-        return;
-      }
-
-      final JPanel panel = new JPanel(new BorderLayout());
-      panel.add(label, BorderLayout.CENTER);
-      final Content content = contentManager.getFactory().createContent(panel, null, false);
-      contentManager.removeAllContents(true);
-      contentManager.addContent(content);
-    });
+    new ViewUtils().replacePanelLabel(contentManager, label);
   }
 
   private BrowserTab openBrowserTabFor(String tabName, ToolWindow toolWindow) {

flutter-idea/src/io/flutter/view/ViewUtils.java

@@ -79,8 +79,11 @@ public void presentClickableLabel(ToolWindow toolWindow, List<LabelInput> labels
   }
 
   public void replacePanelLabel(ToolWindow toolWindow, JComponent label) {
+    replacePanelLabel(toolWindow.getContentManager(), label);
+  }
+
+  public void replacePanelLabel(ContentManager contentManager, JComponent label) {
     OpenApiUtils.safeInvokeLater(() -> {
-      final ContentManager contentManager = toolWindow.getContentManager();
       if (contentManager.isDisposed()) {
         return;
       }