 import mx.core.IIMESupport;
 import mx.core.IUIComponent;
 import mx.core.Singleton;
+import mx.core.UIComponent;
 import mx.core.mx_internal;
 import mx.events.FlexEvent;
 import mx.managers.ISystemManager;

import spark.core.CSSTextLayoutFormat;
import spark.core.IViewport;
import spark.core.ScrollUnit;
import spark.core.TextBaseClassWithStylesAndFocus;
import spark.events.TextOperationEvent;
import spark.primitives.Rect;
import spark.utils.TextUtil;

    /**
     *  @private
     */
    override protected function focusOutHandler(event:FocusEvent):void
    {
        // By default, we clear the undo history when a TextView loses focus.
        if (mx_internal::clearUndoOnFocusOut && mx_internal::undoManager)
