Auto merge of #16672 - nox:moz-force-broken-image-icon, r=emilio

Implement -moz-force-broken-image-icon in geckolib

<!-- Reviewable:start -->
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/16672)
<!-- Reviewable:end -->

2 files changed, 56 insertions, 0 deletions

diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index f3d4d229cec..aa362da1724 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -4041,6 +4041,15 @@ clip-path
     % endfor
 </%self:impl_trait>
 
+<%self:impl_trait style_struct_name="UI" skip_longhands="-moz-force-broken-image-icon">
+    #[allow(non_snake_case)]
+    pub fn set__moz_force_broken_image_icon(&mut self, v: longhands::_moz_force_broken_image_icon::computed_value::T) {
+        self.gecko.mForceBrokenImageIcon = v.0 as u8;
+    }
+
+    ${impl_simple_copy("_moz_force_broken_image_icon", "mForceBrokenImageIcon")}
+</%self:impl_trait>
+
 <%self:impl_trait style_struct_name="XUL"
                   skip_longhands="-moz-stack-sizing -moz-box-ordinal-group">
 
diff --git a/components/style/properties/longhand/ui.mako.rs b/components/style/properties/longhand/ui.mako.rs
index dff6e846050..05808307635 100644
--- a/components/style/properties/longhand/ui.mako.rs
+++ b/components/style/properties/longhand/ui.mako.rs
@@ -30,3 +30,50 @@ ${helpers.single_keyword("-moz-window-dragging", "default drag no-drag", product
                          gecko_enum_prefix="StyleWindowDragging",
                          animation_value_type="none",
                          spec="None (Nonstandard Firefox-only property)")}
+
+<%helpers:longhand name="-moz-force-broken-image-icon"
+                   products="gecko"
+                   animation_value_type="none"
+                   spec="None (Nonstandard Firefox-only property)">
+    use cssparser::Token;
+    use std::fmt;
+    use style_traits::ToCss;
+    use values::HasViewportPercentage;
+    use values::computed::ComputedValueAsSpecified;
+
+    no_viewport_percentage!(SpecifiedValue);
+
+    pub mod computed_value {
+        #[derive(Debug, Clone, Copy, PartialEq)]
+        #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
+        pub struct T(pub bool);
+    }
+
+    pub use self::computed_value::T as SpecifiedValue;
+
+    impl ToCss for computed_value::T {
+        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+            dest.write_str(if self.0 { "1" } else { "0" })
+        }
+    }
+
+    #[inline]
+    pub fn get_initial_value() -> computed_value::T {
+        computed_value::T(false)
+    }
+
+    #[inline]
+    pub fn get_initial_specified_value() -> SpecifiedValue {
+        computed_value::T(false)
+    }
+
+    impl ComputedValueAsSpecified for SpecifiedValue {}
+
+    pub fn parse(_context: &ParserContext, input: &mut Parser) -> Result<SpecifiedValue, ()> {
+        match try!(input.expect_integer()) {
+            0 => Ok(computed_value::T(false)),
+            1 => Ok(computed_value::T(true)),
+            _ => Err(()),
+        }
+    }
+</%helpers:longhand>