[ActivityManager] Reset ActivityRecord's waitingVisible

Symptom:
The ActivityRecord's waitingVisible is not set to false for
all cases when the ActivityRecord is removed from
mStackSupervisor.mWaitingVisibleActivities.

Solution:
Set the waitingVisible to false when it is removed from
mStackSupervisor.mWaitingVisibleActivities

Change-Id: If0f0683971d70a6866b0167e91dd95feebaac178