Fix several bugs causing the page to reflow on every mouse move event
After all these changes are applied, Hacker News and GitHub only repaint and reflow nodes that actually have hover styles applied when the mouse moves over them.
r? @mbrubeck
cc @bholley
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new styles are set.
Tying transitions to the DOM node avoids quadratic complexity when
updating them.
Finishing transitions instantly when styles are updated makes our
behavior more correct.
The util component specified fnv and smallvec as dependencies and publicly
reexported both of them. Several other components utilized these reexports,
presumably because fnv and smallvec used to live in the tree so reexporting
made the transition easier.
These indirect dependencies through the util component are unnecessary.
This commit removes the fnv & smallvec crate reexports in the util component.
It exchange, it adds fnv & smallvec as dependencies to non-util components
wherever needed. Finally, it removes the fnv dependency from util as it is not
utilized anywhere in the util component.
NodeTypeId is supposed to reflect the WebIDL inheritance hierarchy.
All of Text/ProcessingInstruction/Comment inherit from CharacterData,
which inherits from Node. There should be a CharacterDataTypeId value
that differentiates between those, instead.
Transition events are not yet supported, and the only animatable
properties are `top`, `right`, `bottom`, and `left`. However, all other
features of transitions are supported. There are no automated tests at
present because I'm not sure how best to test it, but three manual tests
are included.
When a viewport is resized, the computed values for a style containing viewport percentage length units become stale. However, there's no way for those styles to be invalidated after a resize. As a solution, this commit invalidates the computed values cache after a resize has occurred, which is probably over-kill.
A better solution would probably be to track under what conditions computed values remain valid, and invalidate them as indicated.
