Explicitly set box-sizing to avoid visual bugs when using bootstrap.

[mramato]

As discussed in #2479 when using Bootstrap and Cesium together, the default box-sizing model gets changed on us, which created some visual bugs. After this change, there are still visual differences in our widgets when using bootstrap, but the content sizing issues have been fixed.

[mramato]

CC @emackey fixes #2479

[mramato]

While I was at it, I cleaned up the CSS using Web Essentials:

1. Added missing vendor prefixes
2. Removed no longer needed prefixes
3. Ran auto-formatter

[emackey]

Does Opera still use the -o- prefix now that they've switched to Blink? I thought they ended up using the -webkit- prefix as a result. Cesium was never compatible with Presto and the -o- prefix.

[mramato]

I'm not sure and a quick Google didn't give an answer. We already had the -o- prefix in a bunch of places, and since by default the tool adds them I figured it was better to be consistent. If you are convinced we don't need them, we should remove them all, including the ones that were already there (and next time I use Web Essentials I'll just tell it we don't care about Opera).

[emackey]

Actually I'm tempted to rip out all vendor prefixes for box-sizing, transform, and transition (possibly leaving only user-select, anything else remaining?) Then test the result in IE, FF, Chrome and see if these effects work without their prefixes.

The tool you're using generates the wrong prefixes. For example, on the -o-transition prefixes it generated, it linked to the un-prefixed transform property, where it should have linked to the -o-transform property.

[mramato]

As I said, I have no problem backing out the -o- prefixes, but why hurry and remove the rest? Taking them out buys us nothing and may break old browsers. Or is there some hidden benefit I'm missing?

[emackey]

No hurry to remove the working ones, it's just a pile of old complexity that will only become more obsolete over time. It irks me that automated tools do the "wrong" thing by simply copying the un-prefixed content verbatim into prefixed versions, without taking into account things like vendor-specific syntax differences, or references to other prefixed properties.

[emackey]

But yes you should leave the old ones in for now I guess.

[mramato]

When you get right down to it, I trust your judgment. so feel free to remove whatever you like or make any other changes before merging. If there anything you need from me, let me know.

[emackey]

After much exploring of caniuse and testing in Opera and IE11, this is my current strategy:

• user-select needs prefixes for -ms-, -moz-, and -webkit-.
• box-sizing, transition, transform, and linear-gradient can all keep their -moz- and -webkit- prefixes for now, out-dated though they may be, as old versions do exist that can run Cesium and require these prefixes. But by next year these should all go away.
• box-sizing, transition, transform, and linear-gradient do not need -ms- prefixes, as IE did not support WebGL when it needed those prefixes.
• The -o- prefix is no longer recognized by Opera after its switch to Chromium, and Opera did not run Cesium prior to this switch, so the prefix has been dropped.

It's worth noting that prefixes in general are a legacy system on the web, newer features will use about:config enable flags rather than new prefixes. Prefixes must be curated by hand, as popular tools like Web Essentials will automatically do incorrect things like creating prefixed transitions that use un-prefixed transforms. I expect them to be fully obsolete by 2016, with the possible exception of user-select due to its non-standard status.