Skip setShelfHeight if Launcher is not started

Video: http://recall/-/aaaaaabFQoRHlzixHdtY/gIqsb2WlagwQ8ly3q3RHI0
Bug: 184797356
Test: atest WMShellFlickerTests:PipShelfHeightTest
Test: manual, see video
Change-Id: Ia02b2da110b05341dfbf92b9d8d7fca4bbf6bdb3
1 file changed