[XR][JXR] Code change required to use the JXR alpha04 libraries.

Due to the changes in the JXR APIs the .so files are accessed on loading
hence the androidx.xr.scenecore.Session class cannot be used directly in
the Chrome app as the related .so files are not needed for the app.

Replaced androidx.xr.scenecore.Session by using JxrPlatformAdapterAxr
class to call the related JXR extension apis.

Updated the expectations files due to an addition of a new asset
`black_skybox_android_xr_scenecore.exr` between JXR alpha02 and alpha04
releases which is used on initial loading JXR libraries.

The release notes for moving from alpha02 to alpha04 are -
https://developer.android.com/jetpack/androidx/releases/xr-scenecore#version_10_2.

Recording is here
https://drive.google.com/file/d/1cCGH5eHyWtLbXLsP-WBDY0g84_3bpVTw/view?usp=drive_link&resourcekey=0-c2TY7mlDtecmP80zlvVs9A.

Test: Manually validated all the spatialization related actions works as
before.

Bug: 416529182
Change-Id: I3808369a0cb20550d3e03580069630fcd36fbf50
Fixed: 416529182
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6564452
Reviewed-by: Sam Maier <smaier@chromium.org>
Commit-Queue: Sam Maier <smaier@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Auto-Submit: Gurmeet Kalra <gurmeetk@google.com>
Cr-Commit-Position: refs/heads/main@{#1463432}
NOKEYCHECK=True
GitOrigin-RevId: 38b022cdecf97302270ee5cc892274becaf759ef