A Frame now knows about its nesting-level.
The FrameLoader checks whether the recursion level of the current
frame allows it to be displayed and if not doesn't even load the
requested resource.
The nesting-check is done on a per-URL-basis, so there can be many many
nested Frames as long as they have different URLs.
If there are however Frames with the same URL nested inside each other
we only allow this to happen 3 times.
This mitigates infinetely recursing <iframe>s in an HTML-document
crashing the browser with an OOM.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
The approach of attaching sub-widgets to the web view widget was only
ever going to work in single-process mode, and that's not what we're
about anymore, so let's just get rid of WidgetBox so we don't have the
dead-end architecture hanging over us.
The next step here is to re-implement <input type=text> using LibWeb
primitives.
The WebContent process was redoing page layout every time you scrolled
the page. This was a huge CPU hog for no reason. Fix this by only doing
a relayout when the viewport is resized, not when it moves around.
Also stop exposing the DOM cursor as a mutable reference on Frame,
since event handling code was using that to mess with the text offset
directly. Setting the cursor now always goes through the Frame where
we can reset the blink cycle appropriately.
This makes cursor movement look a lot more natural. :^)
Image boxes want to know whether they are inside the visible viewport.
This is used to pause/resume animations, and to update the purgeable
memory volatility state.
Previously we would traverse the entire layout tree on every resize,
calling a helper on each ImageBox. Make those boxes register with the
frame they are interested in instead, saving us all that traversal.
This also makes it easier for other parts of the code to learn about
viewport changes in the future. :^)
