This enables it to be compiled without libservo:
```
cargo build --manifest-path components/script/Cargo.toml
```
… and then to be added to http://perf.rust-lang.org/
Mention that we need Python3 to build on CentOS
Mention that we need Python3 to build on CentOS
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Avoid decoding XHR type="json" responses as UTF-16BE/LE
https://infra.spec.whatwg.org/#parse-json-from-bytes says to use
"UTF-8 decode" rather than "decode", so UTF-16BE/LE BOM should
not be honored.
CC @SimonSapin
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changed f64 to u64 for navigation start timing until it had to be float
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style: Move font-weight outside of mako
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