Auto merge of servo#233 - nox:ice, r=SimonSapin

Work around an unfortunate ICE

rust-lang/rust#37274

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Auto merge of servo#216 - nox:serde, r=SimonSapin

Allow serde 0.8 and remove use of compiler plugins

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Auto merge of servo#198 - servo:empty-path, r=mbrubeck

Have Url::from_file_path not generate an URL with an empty path. Fix servo#197

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Auto merge of servo#189 - servo:defer-mutate-path-segments, r=nox

Defer mutate path segments

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Auto merge of servo#175 - nox:unbump-heapsize, r=SimonSapin

Unbump heapsize_plugin to 0.1.0

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Auto merge of servo#168 - nox:heapsize, r=jdm

Allow heapsize 0.3

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Auto merge of servo#165 - nox:heapsize, r=KiChjang

Allow heapsize 0.2

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Use is_combining_mark from unicode_normalization.