This patch moves the Selector object model closer to the specification
objects in Selectors Level 4.
A "Selector" in LibHTML is now a { Vector<ComplexSelector> }, which is
a { Relation, CompoundSelector }. A CompoundSelector is really just
a Vector<SimpleSelector>, and SimpleSelector is "Component" renamed.
This makes a lot more selectors actually match on the Ubuntu Apache2
default homepage. :^)
This patch adds a[foo] and a[foo=bar] attribute selectors.
Note that an attribute selector is an optional part of a selector
component, and not a component on its own.
This patch implements two more selector features:
- "div + p" matches the <p> sibling immediately after a <div>.
- "div ~ p" matches all <p> siblings after a <div>.
"div p" now generates a Selector with two components where the second
component is a type=TagName, value="p", relation=Descendant.
We still don't handle matching of these, but at least we parse them.
The parser now kinda recognizes immediate child selectors, !important,
and various other little things.
It's still extremely far from robust and/or correct. :^)
This was a workaround to be able to build on case-insensitive file
systems where it might get confused about <string.h> vs <String.h>.
Let's just not support building that way, so String.h can have an
objectively nicer name. :^)
