@Override
    public void contentRemoved(@NotNull ContentManagerEvent event) {
      if (event.getContent() == myContent) {
        synchronized (myMessageViewLock) {
          if (myErrorTreeView != null) {
            Disposer.dispose(myErrorTreeView);
            myErrorTreeView = null;
            if (myIndicator.isRunning() && !myIndicator.isCanceled()) {
              myIndicator.cancel();
            }
            if (AppIcon.getInstance().hideProgress(myProject, "compiler")) {
              AppIcon.getInstance().setErrorBadge(myProject, null);
            }
          }
        }
        myContentManager.removeContentManagerListener(this);
        myContent.release();
        myContent = null;
      }
    }
@Override
    public void contentRemoved(@NotNull ContentManagerEvent event)