Tests that device emulation affects fenced frames.
Metrics: {
    screen.height : 600
    screen.orientation.angle : 270
    screen.orientation.type : landscape-secondary
    screen.width : 800
}
FF Metrics: {
    screen.height : 600
    screen.orientation.angle : 270
    screen.orientation.type : landscape-secondary
    screen.width : 800
}