Initialize launchCookie in fillTaskInfo.

- This can cause that some tasks are routed to the wrong TaskListener.
- The TaskInfo can be reused if the previous TaskOrganizerController
  .dispatchTaskInfoChanged() exits in the middle:
    http://shortn/_I3HhUmbKPh

Bug: 177490846
Test: Check if CarLauncher with TaskView starts properly
Change-Id: I76f45c68bf7f9db34259bb6c2651d253505cdc6b

services/core/java/com/android/server/wm/Task.java

@@ -4085,6 +4085,7 @@ class Task extends WindowContainer<WindowContainer> {
         info.topActivityInfo = mReuseActivitiesReport.top != null
                 ? mReuseActivitiesReport.top.info
                 : null;
+        info.launchCookies.clear();
         info.addLaunchCookie(mLaunchCookie);
         forAllActivities(r -> {
             info.addLaunchCookie(r.mLaunchCookie);

services/core/java/com/android/server/wm/TaskOrganizerController.java

@@ -555,6 +555,7 @@ class TaskOrganizerController extends ITaskOrganizerController.Stub {
             changed = (cfgChanges & REPORT_CONFIGS) != 0;
         }
         if (!(changed || force)) {
+            // mTmpTaskInfo will be reused next time.
             return;
         }
         final RunningTaskInfo newInfo = mTmpTaskInfo;