WmTests: fix natural rotation tests

[CeRRiLLo89]

Summary

• Call the statically imported getNaturalRotation() method at the three affected test sites instead of referencing it as a value.
• Make foldableConfigFalse_locksRotation_usesNaturalRotation deterministic by configuring the fake settings provider so the current rotation is not eligible.

Root cause

The test source referenced getNaturalRotation without invoking it, which prevents WmTests from compiling. After correcting those calls, the natural-rotation test could still select USE_CURRENT_ROTATION because the default allowed-rotation mask includes the device's current rotation. Setting ACCELEROMETER_ROTATION_ANGLES to 0 in the fake resolver isolates the natural-rotation branch the test is intended to cover.

This changes test code only; no production behavior is modified.

Validation

• m -j6 WmTests — passed
• atest --serial 112eb247 'WmTests:com.android.server.wm.DeviceStateAutoRotateSettingControllerTests#foldableConfigFalse_locksRotation_usesNaturalRotation' — 1 passed, 0 failed
• atest --serial 112eb247 WmTests:com.android.server.wm.DeviceStateAutoRotateSettingControllerTests — 28 passed, 0 failed

Validation device: Xiaomi Mi 9T Pro / Redmi K20 Pro (raphael), Android 16.

[CeRRiLLo89]

Updated after the recent 16.0 history rewrite.

The branch has been rebuilt directly on the current 16.0 base (15593548c424fbcc4d44b2d07160dbc530ee428d).

Current PR head:
67086319cee9049d7ecdc5f52963a55121397386

The PR is now clean again:

• 1 commit
• 1 changed file
• 6 additions / 3 deletions
• no unrelated changes

The stable patch-id is identical to the previously validated commit, so the actual source change is unchanged.

Ready for review.