Respect the override bounds of the leaf tasks

- #updateOverrideConfigurationFromLaunchBounds ensures the leaf task
  inherits the Task bounds from its organized parent Task, but it is
  called only when a Task (or an Activity) is initially added to the
  WM hierarchy. This is not making sense from policy pov because the
  leaf Task bound can still be updated after the Task is added to the
  hierarchy.
- The design was originally added in commit 06107a36, which was to
  fix a split-screen divider issue back in the day. The split-screen
  design has changed a lot since then and the split-screen still
  works fine after this clean-up.
- We’re seeing more multitasking features toward having an organized
  root task design, and have encountered similar issues that the
  requested launching bounds are not respected.

Bug: 410745462
Test: atest RootTaskTests#testGetVisibility_MultiLevel
Test: atest
MultiWindowTests#testVisibilityWithTranslucentAndTopFinishingActivity
Test: atest
ActivityLifecycleTopResumedStateTests#testTopPositionSwitchOnTap
Test: atest ActivityLifecycleLegacySplitScreenTests
Test: drag divider in split
Flag: com.android.window.flags.respect_leaf_task_bounds

Change-Id: I6462ca0460aa36d6d8d160ba8b8fecf8259d1b1f