Add a command to clear recent apps

This CL adds a command imitating a click to `Clear all` button in Overview, clearing the list of recently used apps.

Test: Run `adb shell am clear-recent-apps`
Bug: 260204765
Change-Id: I442223610acda34349b00956d77c649153a3b815

services/core/java/com/android/server/am/ActivityManagerShellCommand.java

@@ -248,6 +248,8 @@ final class ActivityManagerShellCommand extends ShellCommand {
                     return runForceStop(pw);
                 case "stop-app":
                     return runStopApp(pw);
+                case "clear-recent-apps":
+                    return runClearRecentApps(pw);
                 case "fgs-notification-rate-limit":
                     return runFgsNotificationRateLimit(pw);
                 case "crash":
@@ -1192,6 +1194,11 @@ final class ActivityManagerShellCommand extends ShellCommand {
         return 0;
     }
 
+    int runClearRecentApps(PrintWriter pw) throws RemoteException {
+        mTaskInterface.removeAllVisibleRecentTasks();
+        return 0;
+    }
+
     int runFgsNotificationRateLimit(PrintWriter pw) throws RemoteException {
         final String toggleValue = getNextArgRequired();
         final boolean enable;