style: Remove nsStyleColor moving the color property to nsStyleText.

I think this is a good change regardless of other discussion in bug 1552587. If
we decide to move `mColor` to the top-level of the struct that can be done
separately.

Differential Revision: https://phabricator.services.mozilla.com/D32726

components/style/matching.rs

@@ -718,7 +718,7 @@ pub trait MatchMethods: TElement {
                 let device = context.shared.stylist.device();
 
                 // Needed for the "inherit from body" quirk.
-                let text_color = new_primary_style.get_color().clone_color();
+                let text_color = new_primary_style.get_inherited_text().clone_color();
                 device.set_body_text_color(text_color);
             }
         }

components/style/properties/build.py

@@ -25,7 +25,6 @@
     "background",
     "border",
     "box",
-    "color",
     "column",
     "counters",
     "effects",

components/style/properties/gecko.mako.rs

@@ -3355,9 +3355,6 @@ clip-path
     }
 </%self:impl_trait>
 
-<%self:impl_trait style_struct_name="Color">
-</%self:impl_trait>
-
 <%self:impl_trait style_struct_name="InheritedUI" skip_longhands="cursor">
     pub fn set_cursor(&mut self, v: longhands::cursor::computed_value::T) {
         self.gecko.mCursor = v.keyword;

components/style/properties/longhands/inherited_text.mako.rs

@@ -6,6 +6,16 @@
 <% from data import Keyword %>
 <% data.new_style_struct("InheritedText", inherited=True, gecko_name="Text") %>
 
+${helpers.predefined_type(
+    "color",
+    "ColorPropertyValue",
+    "::cssparser::RGBA::new(0, 0, 0, 255)",
+    animation_value_type="AnimatedRGBA",
+    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    ignored_when_colors_disabled="True",
+    spec="https://drafts.csswg.org/css-color/#color",
+)}
+
 ${helpers.predefined_type(
     "line-height",
     "LineHeight",

components/style/properties/properties.mako.rs

@@ -2832,7 +2832,7 @@ impl ComputedValues {
     ///   style.resolve_color(style.get_border().clone_border_top_color());
     #[inline]
     pub fn resolve_color(&self, color: computed::Color) -> RGBA {
-        color.to_rgba(self.get_color().clone_color())
+        color.to_rgba(self.get_inherited_text().clone_color())
     }
 }
 

components/style/values/specified/color.rs

@@ -645,7 +645,7 @@ impl ToComputedValue for ColorPropertyValue {
     fn to_computed_value(&self, context: &Context) -> RGBA {
         self.0
             .to_computed_value(context)
-            .to_rgba(context.builder.get_parent_color().clone_color())
+            .to_rgba(context.builder.get_parent_inherited_text().clone_color())
     }
 
     #[inline]