Implement DOM to texture
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This is a prototype of the WebGL DOMToTexture feature. The API should be fine as a privileged extension for now due to security concerns. The working group has been investigating the viability of unprivileged usage but the spec is not ready yet.
Demo video: https://www.youtube.com/watch?v=hpZqEM5hPao
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* Add support for clip masks on text runs.
* Fix atomic ordering of items with multiple shadows.
* Update to bincode + ipc-channel with optimizations.
* Fix some plane splitting precision errors.
* Improve the anti-aliasing quality significantly.
* Add internal ClipChain support.
* Fix diacritic glyphs on Linux.
In addition to the sourceMappingURL comment, there is a second special
comment, "sourceURL", that can be used to set the "display name" of a
style sheet for developer tools. This name is also used as the base
URL for the source-map URL resolution algorithm. sourceURL is
described here:
https://blog.getfirebug.com/2009/08/11/give-your-eval-a-name-with-sourceurl/
The devtools feature bug is here:
https://bugzilla.mozilla.org/show_bug.cgi?id=880831
This patch changes servo to preserve and expose this value for use in M-C.
Now that rust-cssparser reports 1-based locations, bump the required
cssparser version and remove get_location_with_offset. Previously,
some code paths were not calling get_location_with_offset; see
https://bugzilla.mozilla.org/show_bug.cgi?id=1398869 for some
background.
Sometimes clippy gets outdated by months, and its current support setup
means that each Servo component need to opt into it by depending on
the plugins crate manually, and not all components do that.
