style: Derive more length stuff, and shrink MaxLength / MozLength's repr(C) representation.

This patch:

 * Makes LengthPercentageOrAuto generic, and removes a bunch of code fo
   LengthPercentageOrNone, which was used only for servo and now can use the
   normal MaxLength (with a cfg() guard for the ExtremumLength variant).

 * Shrinks MaxLength / MozLength's repr(C) reperesentation by reducing enum
   nesting. The shrinking is in preparation for using them from C++ too, though
   that'd be a different bug.

 * Moves NonNegative usage to the proper places so that stuff for them can be
   derived.

I did this on top of bug 1523071 to prove both that it could be possible and
that stuff wasn't too messy. It got a bit messy, but just because of a bug I
had fixed in bindgen long time ago already, so this updates bindgen's patch
version to grab a fix instead of ugly workarounds :)

Differential Revision: https://phabricator.services.mozilla.com/D17762

1 files changed, 6 insertions, 6 deletions

diff --git a/components/style/values/specified/gecko.rs b/components/style/values/specified/gecko.rs
index 8259430bf20..42ca5e3e2bf 100644
--- a/components/style/values/specified/gecko.rs
+++ b/components/style/values/specified/gecko.rs
@@ -5,8 +5,8 @@
 //! Specified types for legacy Gecko-only properties.
 
 use crate::parser::{Parse, ParserContext};
-use crate::values::computed::{self, LengthPercentage};
 use crate::values::computed::length::CSSPixelLength;
+use crate::values::computed::{self, LengthPercentage};
 use crate::values::generics::gecko::ScrollSnapPoint as GenericScrollSnapPoint;
 use crate::values::generics::rect::Rect;
 use crate::values::specified::length::LengthPercentage as SpecifiedLengthPercentage;
@@ -28,8 +28,8 @@ impl Parse for ScrollSnapPoint {
         }
         input.expect_function_matching("repeat")?;
         // FIXME(emilio): This won't clamp properly when animating.
-        let length =
-            input.parse_nested_block(|i| SpecifiedLengthPercentage::parse_non_negative(context, i))?;
+        let length = input
+            .parse_nested_block(|i| SpecifiedLengthPercentage::parse_non_negative(context, i))?;
         Ok(GenericScrollSnapPoint::Repeat(length))
     }
 }
@@ -49,9 +49,9 @@ fn parse_pixel_or_percent<'i, 't>(
                 _ => Err(()),
             }
         },
-        Token::Percentage { unit_value, .. } => Ok(
-            LengthPercentage::new_percent(computed::Percentage(unit_value))
-        ),
+        Token::Percentage { unit_value, .. } => Ok(LengthPercentage::new_percent(
+            computed::Percentage(unit_value),
+        )),
         _ => Err(()),
     };
     value.map_err(|()| location.new_custom_error(StyleParseErrorKind::UnspecifiedError))