Also remove now-dead code that rustc warns about.
It turns out that we lost support for some of our custom URL schemes; I intend
to reimplement them, but I believe this will be significantly easier to do
once the legacy code is out of the way.
Add random Device ID generation
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The [spec](https://webbluetoothcg.github.io/web-bluetooth/#add-an-allowed-bluetooth-device) (2. step) defines that the device id can't be the public address, therefore we generate a random id.
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).
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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because there are no webbluetooth test api implementation yet.
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* Sections like `[dependencies.foo]` can be entries in a `[dependencies]`
section with the `{key = value}` syntax.
* Per-target dependencies can be expressed with more general `cfg(…)`
conditions instead of exact target triples:
https://github.com/rust-lang/cargo/pull/2328
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WebRender has many bugs, and missing features - but it is usable to browse most websites - please report any WebRender specific rendering bugs you encounter!