Added pixelRatio parameter to camera and the frustum objects

[IanLilleyT]

Another CSS pixel fix for #8113

All frustums have a getPixelDimensions function that didn't account for different pixel density displays. So this PR adds a new pixelRatio parameter to these functions. Most systems should pass in frameState.pixelRatio to get a value in css pixels. This fixes a few different files that use minimum/maximum pixel size, including BillboardCollection, Model, Primitive, and PointPrimtiveCollection. This before and after are particularly noticeable on high dpi displays. Toggle the resolution checkbox. In the new version the model stays the same size.

Note: Picking.getPickOrthographicCullingVolume and Picking.getPickPerspectiveCullingVolume pass in 1.0 instead of scene.pixelRatio because picking wants to select from a physically smaller region on higher density screens (aka work with native device pixels instead of css pixels)

[cesium-concierge]

Thanks for the pull request @IanLilleyT!

• ✔️ Signed CLA found.

Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.
• Works (or fails gracefully) in IE11.

[lilleyse]

Before merging this PR make sure to add all the fixed CSS pixels bugs in CHANGES.md

[IanLilleyT]

@lilleyse I made some changes. Now camera uses its own scene's pixel ratio, so the Camera.getPixelSize function signature is the same as pre-PR. Anything that needs the more custom behavior can use camera.frustum.getPixelDimensions and pass in its own pixel ratio.

[hpinkos]

@IanLilleyT @lilleyse what's the status of this? Are we trying to get this in for the release?

[lilleyse]

Yes the plan is to get into the release - I'm good with everything here just need to do some final testing and review. Thanks for the reminder @hpinkos.

[lilleyse]

@IanLilleyT looks good. Write an issue to remove the deprecated function definitions and add the 1.65 label. See #8183 for an example.

[IanLilleyT]

Here's the issue for the deprecation: #8320