There is now an inclusive_descendants_version field of each node, which
increases each time the node, or any of its descendants, is dirtied.
This can be used for cache invalidation, by caching a version number
and comparting the current version number against the cached version number.
This should make it somewhat easier to experiment with alternative
representations in the future. To reduce churn, this commit leaves the String
field public, though.
Also, this will allow us to use the default String type to represent the IDL
USVString type, which explicitly forbids unpaired surrogates, ans as such is
a better match to the Rust String type.
After rebasing, this suddenly became a problem again, even though there's no actual size increase here
(we're shrinking NodeFlags by 1 byte, and adding 1 byte of EventState). Moving the NodeFlags to the end
of Node and the EventState bits to the beginning of Element doesn't seem to helper either.
This is probably a padding issue that's worth investigating at some point, but given the level
of churn in this code it doesn't seem worth it to fuss to much over this right now.
Issue #7365 : test cursor position after clearing selection
In textinput test if the cursor is at the correct position when clearing a selection by press an arrow key.
edit_point is always at the end of the selection, should I test when it's at the beginning ?
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