Added @TestApi to some TaskInfo.java methods

For use in CTS.

Bug: 169271943
Test: MultiWindowTests
Change-Id: Iec98eb93f09ec66c88b4b973b17e559ddc59bee9

core/api/test-current.txt

@@ -292,7 +292,9 @@ package android.app {
   }
 
   public class TaskInfo {
+    method public boolean containsLaunchCookie(@NonNull android.os.IBinder);
     method @NonNull public android.content.res.Configuration getConfiguration();
+    method public int getParentTaskId();
     method @Nullable public android.app.PictureInPictureParams getPictureInPictureParams();
     method @NonNull public android.window.WindowContainerToken getToken();
     method public boolean hasParentTask();

core/java/android/app/TaskInfo.java

@@ -36,6 +36,7 @@ import android.window.TaskSnapshot;
 import android.window.WindowContainerToken;
 
 import java.util.ArrayList;
+import java.util.List;
 import java.util.Objects;
 
 /**
@@ -279,6 +280,24 @@ public class TaskInfo {
         launchCookies.add(cookie);
     }
 
+    /**
+     * @return {@code true} if this task contains the launch cookie.
+     * @hide
+     */
+    @TestApi
+    public boolean containsLaunchCookie(@NonNull IBinder cookie) {
+        return launchCookies.contains(cookie);
+    }
+
+    /**
+     * @return The parent task id of this task.
+     * @hide
+     */
+    @TestApi
+    public int getParentTaskId() {
+        return parentTaskId;
+    }
+
     /** @hide */
     @TestApi
     public boolean hasParentTask() {