Reset NSSL translationY after a transision gets cancelled

We update the translationY of the NSSL upon multiple transitions. If the
Occluded -> LockScreen transition is cancelled, there is no other
transition that is taking over. It causes the NSSL to get stuck with some negative translateY value. This caused the Notifications and the NotificationShelf to be shifted slightly upwards.

This fix resets the translation to 0 if the transition was interrupted
and not completed successfully.

Fixes: 273591201
Test: atest OccludedToLockscreenTransitionViewModelTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:3a23e91c1a76f22ac0da52e942e405525c539b2a)
Merged-In: If0c162a7f1b8a2cf3d261692f5ce333331c36a7b
Change-Id: If0c162a7f1b8a2cf3d261692f5ce333331c36a7b

Author: András Kurucz

packages/SystemUI/src/com/android/systemui/keyguard/ui/viewmodel/OccludedToLockscreenTransitionViewModel.kt

@@ -47,6 +47,7 @@ constructor(
             duration = TO_LOCKSCREEN_DURATION,
             onStep = { value -> -translatePx + value * translatePx },
             interpolator = EMPHASIZED_DECELERATE,
+            onCancel = { 0f },
         )
     }
 

packages/SystemUI/tests/src/com/android/systemui/keyguard/ui/viewmodel/OccludedToLockscreenTransitionViewModelTest.kt

@@ -92,6 +92,21 @@ class OccludedToLockscreenTransitionViewModelTest : SysuiTestCase() {
             job.cancel()
         }
 
+    @Test
+    fun lockscreenTranslationYResettedAfterJobCancelled() =
+        runTest(UnconfinedTestDispatcher()) {
+            val values = mutableListOf<Float>()
+
+            val pixels = 100
+            val job =
+                underTest.lockscreenTranslationY(pixels).onEach { values.add(it) }.launchIn(this)
+            repository.sendTransitionStep(step(0.5f, TransitionState.CANCELED))
+
+            assertThat(values.last()).isEqualTo(0f)
+
+            job.cancel()
+        }
+
     private fun step(
         value: Float,
         state: TransitionState = TransitionState.RUNNING