Animation: Prevent numeric values from becoming negative

[SineSwiper1]

IE8 appears to be fairly strict about erroring out on invalid negative values being put into CSS properties that don't allow negative values. Animation easing methods such as 'easeInOutElastic' will dip into the negative in certain animation frames, and if that CSS property is one of the non-negative values, IE8 will immediately error.

The following CSS properties cannot contain negative values, according to the W3C CSS2.1 standard (and certain CSS3 modules):

• border-spacing
• padding-top, padding-right, padding-bottom, padding-left, and padding
• border-top-width, border-right-width, border-bottom-width, border-left-width, and border-width
• border-top, border-right, border-bottom, border-left, and border (if specifying a width)
• font-size and font (if specifying a size)
• width and height
• min-width, max-width, min-height, and max-height
• line-height
• outline-width and outline (if specifying a width)
• widows

CSS3:

• column-gap and column-rule-width
• device-width, device-height, color, color-index, monochrome
• marquee-play-count
• background-size, border-image-slice, border-image-width, border-image-outset, box-shadow (only the blur radius)

[Scott González]

As on jQuery 1.8, core will handle width, height, padding*, border*Width. We should add support for the other sane values (that means excluding things like widows and marquee-play-count).

[mikesherov]

I'm going to close this as WONTFIX for now. IE9 is the last browser that complains. If anything, we should reopen this against jQuery Compat should users be having actual issues with the remaining uncovered properties in IE8 and IE9.