Fix setView in 2D and CV

[bagnell]

• Seperate set view for the three scene modes.
• Clone input.
• Add more tests to ensure correctness.

For #2943.

[mramato]

Running the sample code in the linked issue seems to cause multiple crashes. Zoom in a little and hit orient north

[hpinkos]

@mramato it doesn't crash for me.

[mramato]

@hpinkos sorry, it only happens if you remove the clone.

This should definitely crash.

var viewer = new Cesium.Viewer('cesiumContainer');

Sandcastle.addToolbarButton('Orient North', function(){
    viewer.scene.camera.setView({
        position: viewer.scene.camera.positionWC,
        roll: 0,
        pitch: -Cesium.Math.PI_OVER_TWO,
        heading: 0
    });
});

[bagnell]

@mramato The crash is fixed.

[mramato]

I updated CHANGES and everything looks good. Thanks.