8u40 b02 and 9 b27.

RTL orientation, ChioceBox popup is not aligned with the ChoiceBox. Different from ComboBox, its right border is on the right side of the snap line.

RT-33696 fix the problem partially. Please compare attached snapshots:
1. choicebox-8u40.png: ChoiceBox 8u40, its right border is on the right side of the snap line.
2. choicebox-8u25.png: ChoiceBox 8u25, without fix of RT-33696.
3. combobox-8u40.png: ComboBox 8u40, its right border is on the left side of the snap line.