Fix panic on opening a directory
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Continued from https://github.com/servo/servo/pull/23548
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Various improvements and update to the http cache
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refactoring with ResourceFetchMetadata
implemented deprecated window.timing functionality
created ResourceTimingListener trait
fixed w3c links in navigation timing
updated include.ini to run resource timing tests on ci
Fixes warnings from rust-lang/rust#44229 when `--enable-commonmark` is
passed to rustdoc.
This is mostly a global find-and-replace for bare URIs on lines by
themselves in doc comments.
