Ensure that pinning an event makes the pinned messages banner appear (#4606)

Author: bmarty

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/MessagesView.kt

@@ -363,7 +363,9 @@ private fun MessagesViewContent(
             },
             content = { paddingValues ->
                 Box(modifier = Modifier.padding(paddingValues)) {
-                    val scrollBehavior = PinnedMessagesBannerViewDefaults.rememberExitOnScrollBehavior()
+                    val scrollBehavior = PinnedMessagesBannerViewDefaults.rememberScrollBehavior(
+                        pinnedMessagesCount = state.pinnedMessagesBannerState.pinnedMessagesCount(),
+                    )
                     TimelineView(
                         state = state.timelineState,
                         timelineProtectionState = state.timelineProtectionState,

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/pinned/banner/PinnedMessagesBannerView.kt

@@ -265,7 +265,7 @@ internal interface PinnedMessagesBannerViewScrollBehavior {
 
 internal object PinnedMessagesBannerViewDefaults {
     @Composable
-    fun rememberExitOnScrollBehavior(): PinnedMessagesBannerViewScrollBehavior = remember {
+    fun rememberScrollBehavior(pinnedMessagesCount: Int): PinnedMessagesBannerViewScrollBehavior = remember(pinnedMessagesCount) {
         ExitOnScrollBehavior()
     }
 }