Controls UI - Do not clear callbacks on user change

Listeners would get into an invalid state when changing users.

Fixes: 155990179
Test: atest ControlsListingControllerImplTest
Change-Id: I9c48c767a7da47eca029a27f9c223e92c2359412

packages/SystemUI/src/com/android/systemui/controls/management/ControlsListingControllerImpl.kt

@@ -106,9 +106,15 @@ class ControlsListingControllerImpl @VisibleForTesting constructor(
 
     override fun changeUser(newUser: UserHandle) {
         backgroundExecutor.execute {
-            callbacks.clear()
-            availableServices = emptyList()
             serviceListing.setListening(false)
+
+            // Notify all callbacks in order to clear their existing state prior to attaching
+            // a new listener
+            availableServices = emptyList()
+            callbacks.forEach {
+                it.onServicesUpdated(emptyList())
+            }
+
             currentUserId = newUser.identifier
             val contextForUser = context.createContextAsUser(newUser, 0)
             serviceListing = serviceListingBuilder(contextForUser)

packages/SystemUI/tests/src/com/android/systemui/controls/management/ControlsListingControllerImplTest.kt

@@ -177,4 +177,31 @@ class ControlsListingControllerImplTest : SysuiTestCase() {
         inOrder.verify(mockSL).setListening(true)
         inOrder.verify(mockSL).reload()
     }
-}
+
+    @Test
+    fun testChangeUserResetsExistingCallbackServices() {
+        val list = listOf(serviceInfo)
+        controller.addCallback(mockCallback)
+
+        @Suppress("unchecked_cast")
+        val captor: ArgumentCaptor<List<ControlsServiceInfo>> =
+                ArgumentCaptor.forClass(List::class.java)
+                        as ArgumentCaptor<List<ControlsServiceInfo>>
+        executor.runAllReady()
+        reset(mockCallback)
+
+        serviceListingCallbackCaptor.value.onServicesReloaded(list)
+
+        executor.runAllReady()
+        verify(mockCallback).onServicesUpdated(capture(captor))
+        assertEquals(1, captor.value.size)
+
+        reset(mockCallback)
+        controller.changeUser(UserHandle.of(otherUser))
+        executor.runAllReady()
+        assertEquals(otherUser, controller.currentUserId)
+
+        verify(mockCallback).onServicesUpdated(capture(captor))
+        assertEquals(0, captor.value.size)
+    }
+}