Auto merge of servo#194 - servo:bad, r=emilio

Fix serialization of bad-string and bad-url tokens

This will help fix https://bugzilla.mozilla.org/show_bug.cgi?id=1396664.

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Auto merge of servo#180 - upsuper:at-rule-parser, r=SimonSapin

Have at-rule without block handled in two stages as well

This change makes `AtRuleParser::parse_prelude` always return a prelude if parsed successfully, so that at-rules which do not accept block can be handled in two phases just like those with block.

This is important because at-rules without block usually have side effects. If `parse_prelude` executes the side effect, but `parse_at_rule` later determined that the rule is actually invalid (e.g. because it is followed by a block), there is no way for impl of `AtRuleParser` to undo the side effect.

It provides the necessary parser side change for fixing [Gecko bug 1388911](https://bugzilla.mozilla.org/show_bug.cgi?id=1388911).

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Auto merge of servo#186 - servo:smolvec, r=emilio

Use a SmallVec instead of Vec in consume_until_end_of_block

… to avoid allocating in common cases.

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Auto merge of servo#181 - servo:skip_whitespace, r=nox

Add Parser::skip_whitespace

(and use it it rule parsing to make it hopefully more efficient.)

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Auto merge of servo#173 - upsuper:number-serialize, r=SimonSapin

Serialize number to no more than necessary precision

I'm not sure whether it can be simplified... and I probably need some more idea for how should I test it... But things look fine so far.

This should probably goes to an independent crate at some point.

It should fix servo/servo#17205.

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Auto merge of servo#178 - tromey:source-map-url, r=SimonSapin

Extract source map URL from directive comments

Change the parser to extract the source map URL from directive comments.
The relevant spec is here:

https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit#heading=h.lmz475t4mvbx

This is part of similar work being done in M-C in
https://bugzilla.mozilla.org/show_bug.cgi?id=1388855

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Auto merge of servo#177 - servo:line-counting, r=emilio

Count line-numbers during tokenization

Before this PR, the `source_location` and `current_source_location` iterated (again) through input bytes separately from tokenization in order to count newline characters and determine the line number of some piece of a stylesheet.

This PR makes this counting happen during tokenization instead, where we already have a pass looking at every bytes.

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Auto merge of servo#176 - servo:bad_url_slice_not_at_char_boundary, r…

…=emilio

Fix another panic in bad-url token parsing

https://bugzilla.mozilla.org/show_bug.cgi?id=1383975

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Auto merge of servo#175 - servo:bad_url_slice_out_of_bounds, r=emilio

Fix a panic in bad-url token parsing. Fix servo#174.

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