Log the trial to start non-current user Activity

It's hard to debug the reason why non-current user's Activity is not
visible. We'd better have the explicit log-message for the case.

Bug: 331137460
Test: atest CtsVirtualDevicesAppLaunchTestCases and check if the log is shown
Change-Id: I423aafd272dff7d4f5b4a4a6a78b613d11785123
1 file changed