servo: Merge #16596 - Handle length parsing mode for other types too (from Manishearth:length-parsing); r=heycam

All length types should handle this. Seems to block a couple tests.

try at https://treeherder.mozilla.org/#/jobs?repo=try&revision=b1eb64509e65f9dc548d361ac2ae00ce000c9d7b

Source-Repo: https://github.com/servo/servo
Source-Revision: fffb94530e6dcdfa021e1d86778ada4c7af2fbb9

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 0f992313f7d18bfc7746d651da90f39bc90d9277

servo/components/style/values/specified/length.rs

@@ -1160,8 +1160,12 @@ impl LengthOrPercentage {
                 NoCalcLength::parse_dimension(context, value.value, unit).map(LengthOrPercentage::Length),
             Token::Percentage(ref value) if num_context.is_ok(value.unit_value) =>
                 Ok(LengthOrPercentage::Percentage(Percentage(value.unit_value))),
-            Token::Number(ref value) if value.value == 0. =>
-                Ok(LengthOrPercentage::zero()),
+            Token::Number(ref value) => {
+                if value.value != 0. && !context.length_parsing_mode.allows_unitless_lengths() {
+                    return Err(())
+                }
+                Ok(LengthOrPercentage::Length(NoCalcLength::Absolute(AbsoluteLength::Px(value.value))))
+            }
             Token::Function(ref name) if name.eq_ignore_ascii_case("calc") => {
                 let calc = try!(input.parse_nested_block(|i| {
                     CalcLengthOrPercentage::parse_length_or_percentage(context, i)
@@ -1284,8 +1288,14 @@ impl LengthOrPercentageOrAuto {
                 NoCalcLength::parse_dimension(context, value.value, unit).map(LengthOrPercentageOrAuto::Length),
             Token::Percentage(ref value) if num_context.is_ok(value.unit_value) =>
                 Ok(LengthOrPercentageOrAuto::Percentage(Percentage(value.unit_value))),
-            Token::Number(ref value) if value.value == 0. =>
-                Ok(Self::zero()),
+            Token::Number(ref value) if value.value == 0. => {
+                if value.value != 0. && !context.length_parsing_mode.allows_unitless_lengths() {
+                    return Err(())
+                }
+                Ok(LengthOrPercentageOrAuto::Length(
+                    NoCalcLength::Absolute(AbsoluteLength::Px(value.value))
+                ))
+            }
             Token::Ident(ref value) if value.eq_ignore_ascii_case("auto") =>
                 Ok(LengthOrPercentageOrAuto::Auto),
             Token::Function(ref name) if name.eq_ignore_ascii_case("calc") => {
@@ -1363,8 +1373,14 @@ impl LengthOrPercentageOrNone {
                 NoCalcLength::parse_dimension(context, value.value, unit).map(LengthOrPercentageOrNone::Length),
             Token::Percentage(ref value) if num_context.is_ok(value.unit_value) =>
                 Ok(LengthOrPercentageOrNone::Percentage(Percentage(value.unit_value))),
-            Token::Number(ref value) if value.value == 0. =>
-                Ok(LengthOrPercentageOrNone::Length(NoCalcLength::zero())),
+            Token::Number(ref value) if value.value == 0. => {
+                if value.value != 0. && !context.length_parsing_mode.allows_unitless_lengths() {
+                    return Err(())
+                }
+                Ok(LengthOrPercentageOrNone::Length(
+                    NoCalcLength::Absolute(AbsoluteLength::Px(value.value))
+                ))
+            }
             Token::Function(ref name) if name.eq_ignore_ascii_case("calc") => {
                 let calc = try!(input.parse_nested_block(|i| {
                     CalcLengthOrPercentage::parse_length_or_percentage(context, i)