Don’t fail CI for warnings on the maintenance branch

Auto merge of servo#233 - servo:unique-atom-const-names, r=SimonSapin

Use unique const names in string_cache_codegen

Auto merge of servo#232 - servo:spring, r=nox

Spring cleaning

Yes, October is in autumn. This is overdue since the spring of a couple years ago.

Auto merge of servo#232 - servo:spring, r=nox

Spring cleaning

Yes, October is in autumn. This is overdue since the spring of a couple years ago.

Auto merge of servo#227 - servo:small-stack, r=nox

Fix initializing the global hash map with a small stack

Fix servo/html5ever#393

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Auto merge of servo#206 - mbrubeck:debug_unreachable, r=KiChjang

Switch to fork of debug_unreachable

Because the original debug_unreachable is abandoned and doesn't work correctly in modern Rust.

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Auto merge of servo#203 - hcpl:update-deps, r=SimonSapin

Update dependencies

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Auto merge of servo#203 - hcpl:update-deps, r=SimonSapin

Update dependencies

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