Fix regression with the closing task leash visibility

- We should actually be showing the transition leash if it was
  previously closing and not hiding it
- There's another case where we hide the opening task surface when
  setting up for the transition, we need to also override this alpha
  if the task was previously visible

Bug: 296242449
Test: Quickswitch quickly between tasks such that we relaunch a pausing/
      closed task
Change-Id: I1416eb261ba9016174f1deefd293d58f64ab05ed
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/recents/RecentsTransitionHandler.java b/libs/WindowManager/Shell/src/com/android/wm/shell/recents/RecentsTransitionHandler.java
index bb65da3..50ba897 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/recents/RecentsTransitionHandler.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/recents/RecentsTransitionHandler.java
@@ -738,8 +738,17 @@
                         final boolean wasClosing = closingIdx >= 0;
                         t.reparent(target.leash, mInfo.getRoot(rootIdx).getLeash());
                         t.setLayer(target.leash, layer);
-                        // Hide the animation leash if not already visible, let listener show it
-                        t.setVisibility(target.leash, !wasClosing);
+                        if (wasClosing) {
+                            // App was previously visible and is closing
+                            t.show(target.leash);
+                            t.setAlpha(target.leash, 1f);
+                            // Also override the task alpha as it was set earlier when dispatching
+                            // the transition and setting up the leash to hide the
+                            t.setAlpha(change.getLeash(), 1f);
+                        } else {
+                            // Hide the animation leash, let the listener show it
+                            t.hide(target.leash);
+                        }
                         ProtoLog.v(ShellProtoLogGroup.WM_SHELL_RECENTS_TRANSITION,
                                 "  opening new leaf taskId=%d wasClosing=%b",
                                 target.taskId, wasClosing);