Auto merge of #152 - Manishearth:rounding, r=emilio

Match float parse rounding with Gecko

See https://bugzilla.mozilla.org/show_bug.cgi?id=1366977

r? @SimonSapin

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Author: bors-servo

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 
 name = "cssparser"
-version = "0.13.6"
+version = "0.13.7"
 authors = [ "Simon Sapin <simon.sapin@exyr.org>" ]
 
 description = "Rust implementation of CSS Syntax Level 3"

src/css-parsing-tests/component_value_list.json

@@ -264,12 +264,12 @@
 	["percentage", "12", 12, "integer"], " ",
 	["percentage", "+34", 34, "integer"], " ",
 	["percentage", "-45", -45, "integer"], " ",
-	["percentage", "0.67", 0.67, "number"], " ",
+	["percentage", "0.66999996", 0.67, "number"], " ",
 	["percentage", "+0.89", 0.89, "number"], " ",
 	["percentage", "-0.01", -0.01, "number"], " ",
-	["percentage", "2.3", 2.3, "number"], " ",
-	["percentage", "+45.0", 45, "number"], " ",
-	["percentage", "-0.67", -0.67, "number"]
+	["percentage", "2.3", 2.3000000000, "number"], " ",
+	["percentage", "+45.0", 45.0, "number"], " ",
+	["percentage", "-0.66999996", -0.67, "number"]
 ],
 
 "12e2% +34e+1% -45E-0% .68e+3% +.79e-1% -.01E2% 2.3E+1% +45.0e6% -0.67e0%", [
@@ -281,7 +281,7 @@
 	["percentage", "-1.0", -1, "number"], " ",
 	["percentage", "23.0", 23, "number"], " ",
 	["percentage", "+45000000.0", 45000000, "number"], " ",
-	["percentage", "-0.67", -0.67, "number"]
+	["percentage", "-0.66999996", -0.67, "number"]
 ],
 
 "12\\% /* Percent sign can not be escaped */", [

src/tokenizer.rs

@@ -859,7 +859,7 @@ fn consume_numeric<'a>(tokenizer: &mut Tokenizer<'a>) -> Token<'a> {
     if !tokenizer.is_eof() && tokenizer.next_byte_unchecked() == b'%' {
         tokenizer.advance(1);
         return Percentage(PercentageValue {
-            unit_value: value as f32 / 100.,
+            unit_value: (value / 100.) as f32,
             int_value: int_value,
             has_sign: has_sign,
         })