Changed clipping in TextBox and TextGraphic.as
TextFlowComposer no longer relies on TextLineFactory.createTextLinesFromTextFlow() returning an 'overset' flag, because TLF will be removing this. Instead, it determines whether any TextLines are overset by looking at whether the getBounds() of the container parenting the TextLines is contained inside the composition bounds.
TextBlockComposer now uses identical logic to do this.
TextBox and TextGraphic now call a new method, clip(), in their TextGraphicElement base class to set or clear the scrollRect based on the overset flag. This logic has been further optimized to avoid creating a new Rectangle instance if the scrollRect has already been set.
NOTE: This change was previously committed as revision 4631 and then reverted as revision 4635.
QE Notes: None
Doc Notes: None