When it is called inside `box.for_each_child`, then it may not be called
for the root element. By missing `SVGSVGBox::before_children_paint`
the svg context is not created
The current implementation is missing the emphasized text of the
following rule in the painting order spec:
7. Otherwise: *first for the element*, then for all its in-flow,
non-positioned, block-level descendants in tree order...
This ensures the foreground is painted for the current element before
descending into its children.
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 *
When hit testing a stacked context, skip hit testing children if the
child's z-index is less than the parent's. The children are already
sorted by z-index, but also need to consider the parent.
(...and ASSERT_NOT_REACHED => VERIFY_NOT_REACHED)
Since all of these checks are done in release builds as well,
let's rename them to VERIFY to prevent confusion, as everyone is
used to assertions being compiled out in release.
We can introduce a new ASSERT macro that is specifically for debug
checks, but I'm doing this wholesale conversion first since we've
accumulated thousands of these already, and it's not immediately
obvious which ones are suitable for ASSERT.
