the anchor name as a parameter, so it can look in the correct bin.
In the case of FreeAttrs, we have the name already (since we found a name or
id attribute). In the case of FixAnchors, the anchor name could come from
either the name or id attribute, so we call the function separately for each
case, passing the appropriate attribute value.
Introduced TY_(IsHTMLSpace)(uint c), which checks to see if c is one of the
chars that the HTML spec (and browsers) treat as a space in attribute
values: 0x020 (space), 0x009 (tab), 0x00a (LF), 0x00c (FF), or 0x00d (CF).
Can't use ANSI C isspace(int c) here because like standard functions for
many other langs, it also treats 0x00b as a space.