Fixes OpaLayoutTest to pass by adding SysuiTestCase (1/2)

Copied SysuiTestCase to systemui Google to be able to inflate
KeyButtonView that is dependent on StatusBar. Also fixed the connection
failure catch exception when proxy cannot connect to service in tests.

Test: atest com.google.android.systemui.OpaLayoutTest
Change-Id: Ica2a894ce92e06af30c208afcc6a22adeac3a843
Fixes: 76416916