bf590fe7c9
Introduce GameSession#onGameTaskFocusChanged method that is called to inform GameSession implementations abouts when their game task goes into our out of focus. Also introduce a new LifecycleState to the abstract GameSession class to ensure that transitions follow the following rules: - All GameSessions start in the INITIALIZED state - All GameSessions will then transition to the CREATED state [onCreate() is called]. If a GameSession transitions from INITIALIZED directly to DESTOYED, onCreate() and onDestroy() will both be called. - A GameSession in the CREATED state may transition to either the TASK_FOCUSED state [onGameTaskFocusChanged(true) is called] or the DESTROYED state [onDestroy() is called]. If a game task starts in a non-focused state and never comes into focus, the GameSession will never transition to the TASK_FOCUSED or TASK_UNFOCUSED states. - A GameSession in the TASK_FOCUSED state may only transition to the TASK_UNFOCUSED state [onGameTaskFocusChanged(false) is called]. If a GameSession transitions from TASK_FOCUSED to DESTROYED, it will call onGameTaskFocusChanged(false) to complete that part of the lifecycle before transitioning to the DESTROYED state. - A GameSession in the TASK_UNFOCUSED state may transition back to the TASK_FOCUSED state [onGameTaskFocusChanged(false) is called again] or the DESTROYED state [onDestroy() is called]. In this way, all GameSessions are guaranteed to have onGameTaskFocusChanged(true) be called if they are ever in focus before being destroyed (generally as soon as the GameSession is created) and to have onGameTaskFocusChanged(false) be called before they are destroyed. GameSessions are also guarnateed to have onCreate() be called before onDestroy(). Test: Manual e2e testing Bug: 214104366 Bug: 202414447 Bug: 202417255 CTS-Coverage-Bug: 206128693 Change-Id: Id4e1eec50eb891ffb6df74650c27ea3a27a8b9c3