After looking at a handful of websites, the # of Text and Commend nodes
that are small (<= 12 bytes) is _really_ high. Ranging from 85% to 98%. I
thought that was high, but a lot of it is indentation or a sentence that's
broken down into multiple nodes, eg:
<div><b>sale!</b> <span class=price>$1.99</span> buy now<div>
So what looks like 1 sentence to us, is actually 3 text nodes.
On a typical website, we should see thousands of fewer allocations in the
page arena for the text in text nodes.
Avoids having to allocate small strings when going from v8 -> Zig. Also
added a discriminatory type, string.Global which uses the arena, rather than
the call_arena, if an allocation _is_ necessary. (This is similar to a feature
we had before, but was lost in zigdom). Strings from v8 that need to be
persisted, can be allocated directly v8 -> arena, rather than v8 -> call_arena
-> arena.
I think there are a lot of places where we should use string.String - where
strings are expected to be short (e.g. attribute names). But started with just
document.querySelector and querySelectorAll.
