Implement the Request API
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This PR implements the [Request API](https://fetch.spec.whatwg.org/#request-class) for the Fetch API, including its attributes and constructor, and introduces changes in relevant files.
This Request integrates `net_traits::request::Request` and `dom::headers`.
There are few related TODOs and comments:
1. `net_traits::request::Request`'s `headers` field does not point to `dom::request::Request`'s `headers_reflector`.
2. Every Constructor step that involves `Readable Stream` object is not implemented.
3. Every Constructor step that involves `entry settings object` or `environment settings object` is not implemented.
4. `./mach build -d` does not report any error, but prints a few warnings about unused variables related to (1) and (2).
5. Enum `ReferrerPolicy` generated by `RequestBinding` does not match `net_traits::request::Request`'s implementation.
6. `Promise`s in Body webidl are commented out.
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#11895 (github issue number if applicable).
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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because tests for the Request API already exists, but this commit does not implement the interface fully.
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This commit adds new files related to implementing the [Request
API](https://fetch.spec.whatwg.org/#request-class). This commit also
changes the expected web platform tests results. It also modifies the
following files:
components/net_traits/request.rs
HeapSizeOf is implemented in net_traits/request so that dom::request can
be used as a wrapper around net_traits::request::Request.
components/script/dom/headers.rs
Several methods are added to Headers so that request can access and
modify some of the headers fields.
- Hack to stop hitting unreachable on referer
- add fetch_done to make sync work
- Make datauris work by setting the response URI, spec bug
- Allow for empty bodies
- Make request bodies work (pass to http, fix fencepost in iter count)
The current logic for a cors cache match does not consider "credentials
is false and request's credentials mode is not "include" or credentials
is true."
In function Request::fetch_main, flag local_urls_only (if set)
should allow fetching local urls only. Before this change, the flag had
the inverse behaviour.
