As part of [Bug 1172987](https://bugzilla.mozilla.org/show_bug.cgi?id=1172897) we renamed TabActor, as the actor does not represent tabs (as in a browser tab), it instead represents a browsing context as defined by the the [HTML standard](https://html.spec.whatwg.org/multipage/browsers.html#windows). In a later PR I will mirror the structure we have on devtools to have a targets folder, which contains all target types. At the moment it looks like servo only represents workers and browsing contexts.
Use try syntax for Option where appropriate
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because they are refactoring only
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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.
Sometimes clippy gets outdated by months, and its current support setup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.
0) Advertise support for the network monitor in the initial protocol communication.
1) Only notify the developer tools server about the final request in an HTTP transaction.
2) Add timing information for connecting to the HTTP server and sending the HTTP request.
3) Reduce duplication between various networkEventUpdate structures by creating a helper function
that merges two JSON structures together. This also corrects the JSON structure so the devtools
client interprets the output correctly.
4) Calculate various header size fields correctly.
5) Remove unnecessary usize->u32 casts by making the appropriate fields usize.
6) Add header values to request and response header messages.
7) Support triggering page reloads via the devtools client.
