Bring the names of various boxes closer to spec language. This should
hopefully make things easier to understand and hack on. :^)
Some notable changes:
- LayoutNode -> Layout::Node
- LayoutBox -> Layout::Box
- LayoutBlock -> Layout::BlockBox
- LayoutReplaced -> Layout::ReplacedBox
- LayoutDocument -> Layout::InitialContainingBlockBox
- LayoutText -> Layout::TextNode
- LayoutInline -> Layout::InlineNode
Note that this is not strictly a "box tree" as we also hang inline/text
nodes in the same tree, and they don't generate boxes. (Instead, they
contribute line box fragments to their containing block!)
To implement form controls internally in LibWeb (necessary for multi
process forms), we'll need the ability to handle events since we can't
rely on LibGUI widgets anymore.
A LayoutNode can now override wants_mouse_events() and if it returns
true, it will now receive mousedown, mousemove and mouseup events. :^)
You can now cycle through focusable elements (currently only hyperlinks
are focusable) with the Tab key.
The focus outline is rendered in a new FocusOutline paint phase.
This works everywhere right now, but it's obviously not going to stay
that way forever. :^)
Note that this does not advance the cursor correctly for whitespace
since the cursor is DOM-based and doesn't take whitespace collapsing
into account yet.
