Bug 1112416 - Fix racing of InputMgmt/KBApp when switching from RocketBar to other app

- Through a flag in InputWindow, do not really set the iW as inactive during iW's inputapp-closed event if we know it will become ready soon.
- Also, AppTransitionController should not automatically setVisible(false) for InputWindow on "closed".
Merge pull request #26838 from mnjul/bug_1112416_rocketbar_app_inputmgnt_racing

Bug 1112416 - Fix racing of InputMgmt/KBApp when switching from RocketBar to other app. r=timdream