Merge animation transaction of app window to transition

When starting a no animation activity which contains a dialog with
animation:

Transition#onTransactionReady
 > commitVisibleActivities > AR#commitFinishDrawing
 > WS#performShowLocked > WSA#applyEnterAnimationLocked
 > Apply animation if the window is not activity main window.
   e.g. TYPE_APPLICATION from dialog.

The activity doesn't have transition animation. The transition makes
the window surfaces of activity visible directly. If the window level
animation is applied by pending transaction, the reparent of animation
leash may happen at a frame later, which looks like it flickers a frame
and then starts the animation.

Bug: 355578719
Flag: EXEMPT bugfix
Test: Launch an activity in the same task with showing a dialog.
      E.g. Enter "App info" and press "Uninstall".
      The dialog window should not be visible directly before
      starting the fade-in animation.
Change-Id: Ie0d0a6829d451ffd907a74569d7e1476f299ef19