Implement non-zero dimension attribute parsing
Fixes#8445
The only attributes I found that we have implemented that uses non-zero
dimenion attributes:
* `width` for `<td>` and `<th>` (table cells)
* `width` for `<table>`
I updated these implementations to use the new non-zero dimension
attribute parsing and added associated regression tests.
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This patch does a number of things, unfortunately all at once:
* Hoists a large subset of the layout wrapper functionality into the style system.
* Merges TElementAttributes into the newly-created TElement.
* Reorganizes LayoutData by style vs layout, and removes LayoutDataShared.
* Simplifies the API for borrowing style/layout data.
There's still more to do to make the style system usable standalone, but
this is a good start.
Fixes#8445
The only attributes I found that we have implemented that uses non-zero
dimenion attributes:
* `width` for `<td>` and `<th>` (table cells)
* `width` for `<table>`
I updated these implementations to use the new non-zero dimension
attribute parsing and added associated regression tests.
I don't think there is any reason to keep the container more generic
than its (only) implementation -- the constraints are necessary for this
container to work at all.
Defining the constraints on the type itself also enables use
of #[derive(Debug)].
Updated string_cache, html5ever, xml5ever and selectors in Cargo.toml files and Cargo.lock.
Removed references to string_cache_plugin.
Import atom! and ns! from string_cache.
Replaced ns!("") by ns!().
Replaced ns!(XML) and co by ns!(xml) and co.
Replaced atom!(foo) by atom!("foo").
Replaced Atom::from_slice by Atom::from.
Replaced atom.as_slice() by &*atom.
Use the PrintTree utility to improve the readability of flow tree
dumps. Blocks and fragments are now split over two dump levels, because
otherwise they are impenetrable. Also start printing the restyle damage of
fragments.
compositing: Split Servo up into multiple sandboxed processes.
Multiprocess mode is enabled with the `-M` switch, and sandboxing is
enabled with the `-S` switch.
Rebase of #6884.
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The methods which are currently implemented are the ones on String that are currently being used:
string.push_str(...), string.clear() and string.extend(...). We may want to revisit this API.
This implements #7158 by conditionally choosing a UA string by
`#[cfg()]`-checking for `target_os = linux` and whether `target_arch` is
`x86_64` or not. Matching the behavior of Firefox, either "X11; Linux
x86_64" or "X11; Linux i686" is included.
`target_os = windows` is also checked; again as in Firefox "Windows NT
6.1; Win64; x64" or just "Windows NT 6.1" is included. The UA string
pretends to be non-WoW64 Windows 7, since there's only so much we can
detect at build time.
The existing desktop UA string that lists OS X is chosen if `target_os`
is neither `linux` nor `windows`.
