[4/n] Add User Aspect Ratio Button

Adds the  compat ui button which allows users to reach the app info
page in settings and change the aspect ratio for a selected app.

When the feature is enabled, the button appears every time the app is
launched and when TaskInfo.topActivityEligibleForUserAspectRatioButton
and TaskInfo.topActivityBoundsLetterboxed are both true.

The icons appears after a short interval and disappears after 4 seconds.

Fix: 287460588
Test: `atest WMShellUnitTests:UserAspectRatioSettingsWindowManagerTest`
      `atest WMShellUnitTests:UserAspectRatioSettingsLayoutTest`
      `atest WMShellUnitTests:CompatUIControllerTest`
      `atest WMShellUnitTests:ReachabilityEduWindowManagerTest`
      `atest WmTests:LetterboxUiControllerTest`

Change-Id: If1ed5442359b0bc3f352d3b2f9678a5921c73114