Handle specialized serialization of <position> in basic shapes
Fixes#13083
We temporarily broke basic-shape serialization in #13042 when 4-value positions were implemented, since I didn't want to increase the scope of that PR too much.
This fixes it.
r? @SimonSapin
cc @canaltinova
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Handle 3- and 4- valued <position>s in style
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This is first part of fix#12690 and covers just specified style part for now.
r? @Manishearth
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12902 typedefs
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Using type alias instead of newtype.
Removing duplicated implementation, it's already inherited.
No more type constructors and foo.0
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Merge normal and important declarations in style rules
Have a single Vec instead of two. Fix#3426
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The style candidate cache had regressed a few times (see #12534), and my
intuition is that being able to disable all style sharing with a single rule in
the page is really unfortunate.
This commit redesigns the style sharing cache in order to be a optimistic cache,
but then reject candidates if they match different sibling-affecting selectors
in the page, for example.
So far the numbers have improved, but not so much as I'd wanted (~10%/20% of
non-incremental restyling time in general). The current implementation is really
dumb though (we recompute and re-match a lot of stuff), so we should be able to
optimise it quite a bit.
I have different ideas for improving it (that may or may not work), apart of the
low-hanging fruit like don't re-matching candidates all the time but I have to
measure the real impact.
Also, I need to verify it against try.
