Add two test cases:

1. Enter desktop mode with app handle bar
2. Exit desktop mode to full screen with app header

Test: USE_RBE=false atest WMShellFlickerTestsDesktopMode:com.android.wm.shell.flicker.fundamentals.EnterDesktopWithAppHandleMenuFlickerTest -c (http://ab/I00900010406409415)
Test: USE_RBE=false atest WMShellFlickerTestsDesktopMode:com.android.wm.shell.flicker.fundamentals.ExitDesktopToFullScreenWithAppHeaderMenuFlickerTest -c (http://ab/I18000010406455663)
Video: http://recall/-/fEwlogyRdPbYkU9HeEhzVK
Flag: EXEMPT add new test case
Bug: 399823963
Bug: 418206192

Change-Id: Id0546c201ba75256e1d2afb1a307ac1c6c842ad7