Auto merge of #20647 - emilio:gecko-sync, r=emilio

style: Sync changes from mozilla-central.

Se each individual commit for details.

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---
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components/style/properties/data.py

@@ -145,6 +145,17 @@ def arg_to_bool(arg):
     return arg == "True"
 
 
+def parse_property_aliases(alias_list):
+    result = []
+    if alias_list:
+        for alias in alias_list.split():
+            (name, _, pref) = alias.partition(":")
+            if name.startswith("-webkit-") and not pref:
+                pref = "layout.css.prefixes.webkit"
+            result.append((name, pref))
+    return result
+
+
 class Longhand(object):
     def __init__(self, style_struct, name, spec=None, animation_value_type=None, keyword=None,
                  predefined_type=None, servo_pref=None, gecko_pref=None,
@@ -178,8 +189,8 @@ def __init__(self, style_struct, name, spec=None, animation_value_type=None, key
         self.gecko_ffi_name = gecko_ffi_name or "m" + self.camel_case
         self.cast_type = cast_type
         self.logical = arg_to_bool(logical)
-        self.alias = alias.split() if alias else []
-        self.extra_prefixes = extra_prefixes.split() if extra_prefixes else []
+        self.alias = parse_property_aliases(alias)
+        self.extra_prefixes = parse_property_aliases(extra_prefixes)
         self.boxed = arg_to_bool(boxed)
         self.flags = flags.split() if flags else []
         self.allowed_in_page_rule = arg_to_bool(allowed_in_page_rule)
@@ -322,8 +333,8 @@ def __init__(self, name, sub_properties, spec=None, servo_pref=None, gecko_pref=
         self.sub_properties = sub_properties
         assert enabled_in in ["", "ua", "chrome", "content"]
         self.enabled_in = enabled_in
-        self.alias = alias.split() if alias else []
-        self.extra_prefixes = extra_prefixes.split() if extra_prefixes else []
+        self.alias = parse_property_aliases(alias)
+        self.extra_prefixes = parse_property_aliases(extra_prefixes)
         self.allowed_in_page_rule = arg_to_bool(allowed_in_page_rule)
         self.flags = flags.split() if flags else []
 
@@ -373,13 +384,13 @@ def nscsspropertyid(self):
 
 
 class Alias(object):
-    def __init__(self, name, original):
+    def __init__(self, name, original, gecko_pref):
         self.name = name
         self.ident = to_rust_ident(name)
         self.camel_case = to_camel_case(self.ident)
         self.enabled_in = original.enabled_in
         self.servo_pref = original.servo_pref
-        self.gecko_pref = original.gecko_pref
+        self.gecko_pref = gecko_pref
         self.allowed_in_page_rule = original.allowed_in_page_rule
         self.allowed_in_keyframe_block = original.allowed_in_keyframe_block
 
@@ -462,8 +473,12 @@ def add_prefixed_aliases(self, property):
         # FIXME Servo's DOM architecture doesn't support vendor-prefixed properties.
         #       See servo/servo#14941.
         if self.product == "gecko":
-            for prefix in property.extra_prefixes:
-                property.alias.append('-%s-%s' % (prefix, property.name))
+            for (prefix, pref) in property.extra_prefixes:
+                # All webkit prefixed properties are currently under
+                # control of this pref in Gecko currently.
+                if prefix == "webkit" and not pref:
+                    pref = "layout.css.prefixes.webkit"
+                property.alias.append(('-%s-%s' % (prefix, property.name), pref))
 
     def declare_longhand(self, name, products="gecko servo", **kwargs):
         products = products.split()
@@ -472,7 +487,7 @@ def declare_longhand(self, name, products="gecko servo", **kwargs):
 
         longhand = Longhand(self.current_style_struct, name, **kwargs)
         self.add_prefixed_aliases(longhand)
-        longhand.alias = list(map(lambda x: Alias(x, longhand), longhand.alias))
+        longhand.alias = list(map(lambda (x, p): Alias(x, longhand, p), longhand.alias))
         self.longhand_aliases += longhand.alias
         self.current_style_struct.longhands.append(longhand)
         self.longhands.append(longhand)
@@ -488,7 +503,7 @@ def declare_shorthand(self, name, sub_properties, products="gecko servo", *args,
         sub_properties = [self.longhands_by_name[s] for s in sub_properties]
         shorthand = Shorthand(name, sub_properties, *args, **kwargs)
         self.add_prefixed_aliases(shorthand)
-        shorthand.alias = list(map(lambda x: Alias(x, shorthand), shorthand.alias))
+        shorthand.alias = list(map(lambda (x, p): Alias(x, shorthand, p), shorthand.alias))
         self.shorthand_aliases += shorthand.alias
         self.shorthands.append(shorthand)
         return shorthand

components/style/properties/longhand/box.mako.rs

@@ -226,6 +226,8 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
     pub use super::overflow_x::{SpecifiedValue, parse, get_initial_value, computed_value};
 </%helpers:longhand>
 
+<% transition_extra_prefixes = "moz:layout.css.prefixes.transitions webkit" %>
+
 ${helpers.predefined_type("transition-duration",
                           "Time",
                           "computed::Time::zero()",
@@ -234,7 +236,7 @@ ${helpers.predefined_type("transition-duration",
                           vector=True,
                           need_index=True,
                           animation_value_type="none",
-                          extra_prefixes="moz webkit",
+                          extra_prefixes=transition_extra_prefixes,
                           spec="https://drafts.csswg.org/css-transitions/#propdef-transition-duration")}
 
 ${helpers.predefined_type("transition-timing-function",
@@ -244,7 +246,7 @@ ${helpers.predefined_type("transition-timing-function",
                           vector=True,
                           need_index=True,
                           animation_value_type="none",
-                          extra_prefixes="moz webkit",
+                          extra_prefixes=transition_extra_prefixes,
                           spec="https://drafts.csswg.org/css-transitions/#propdef-transition-timing-function")}
 
 ${helpers.predefined_type(
@@ -257,7 +259,7 @@ ${helpers.predefined_type(
     need_index=True,
     needs_context=False,
     animation_value_type="none",
-    extra_prefixes="moz webkit",
+    extra_prefixes=transition_extra_prefixes,
     spec="https://drafts.csswg.org/css-transitions/#propdef-transition-property",
 )}
 
@@ -268,10 +270,12 @@ ${helpers.predefined_type("transition-delay",
                           vector=True,
                           need_index=True,
                           animation_value_type="none",
-                          extra_prefixes="moz webkit",
+                          extra_prefixes=transition_extra_prefixes,
                           spec="https://drafts.csswg.org/css-transitions/#propdef-transition-delay")}
 
 
+<% animation_extra_prefixes = "moz:layout.css.prefixes.animations webkit" %>
+
 ${helpers.predefined_type(
     "animation-name",
     "AnimationName",
@@ -280,7 +284,7 @@ ${helpers.predefined_type(
     vector=True,
     need_index=True,
     animation_value_type="none",
-    extra_prefixes="moz webkit",
+    extra_prefixes=animation_extra_prefixes,
     allowed_in_keyframe_block=False,
     spec="https://drafts.csswg.org/css-animations/#propdef-animation-name",
 )}
@@ -293,7 +297,7 @@ ${helpers.predefined_type("animation-duration",
                           vector=True,
                           need_index=True,
                           animation_value_type="none",
-                          extra_prefixes="moz webkit",
+                          extra_prefixes=animation_extra_prefixes,
                           spec="https://drafts.csswg.org/css-transitions/#propdef-transition-duration")}
 
 // animation-timing-function is the exception to the rule for allowed_in_keyframe_block:
@@ -305,7 +309,7 @@ ${helpers.predefined_type("animation-timing-function",
                           vector=True,
                           need_index=True,
                           animation_value_type="none",
-                          extra_prefixes="moz webkit",
+                          extra_prefixes=animation_extra_prefixes,
                           allowed_in_keyframe_block=True,
                           spec="https://drafts.csswg.org/css-transitions/#propdef-animation-timing-function")}
 
@@ -317,7 +321,7 @@ ${helpers.predefined_type(
     vector=True,
     need_index=True,
     animation_value_type="none",
-    extra_prefixes="moz webkit",
+    extra_prefixes=animation_extra_prefixes,
     allowed_in_keyframe_block=False,
     spec="https://drafts.csswg.org/css-animations/#propdef-animation-iteration-count",
 )}
@@ -330,7 +334,7 @@ ${helpers.single_keyword("animation-direction",
                          vector=True,
                          gecko_enum_prefix="PlaybackDirection",
                          custom_consts=animation_direction_custom_consts,
-                         extra_prefixes="moz webkit",
+                         extra_prefixes=animation_extra_prefixes,
                          spec="https://drafts.csswg.org/css-animations/#propdef-animation-direction",
                          allowed_in_keyframe_block=False)}
 
@@ -339,7 +343,7 @@ ${helpers.single_keyword("animation-play-state",
                          need_index=True,
                          animation_value_type="none",
                          vector=True,
-                         extra_prefixes="moz webkit",
+                         extra_prefixes=animation_extra_prefixes,
                          spec="https://drafts.csswg.org/css-animations/#propdef-animation-play-state",
                          allowed_in_keyframe_block=False)}
 
@@ -349,7 +353,7 @@ ${helpers.single_keyword("animation-fill-mode",
                          animation_value_type="none",
                          vector=True,
                          gecko_enum_prefix="FillMode",
-                         extra_prefixes="moz webkit",
+                         extra_prefixes=animation_extra_prefixes,
                          spec="https://drafts.csswg.org/css-animations/#propdef-animation-fill-mode",
                          allowed_in_keyframe_block=False)}
 
@@ -360,7 +364,7 @@ ${helpers.predefined_type("animation-delay",
                           vector=True,
                           need_index=True,
                           animation_value_type="none",
-                          extra_prefixes="moz webkit",
+                          extra_prefixes=animation_extra_prefixes,
                           spec="https://drafts.csswg.org/css-animations/#propdef-animation-delay",
                           allowed_in_keyframe_block=False)}
 
@@ -397,9 +401,11 @@ ${helpers.predefined_type(
     allow_empty="NotInitial"
 )}
 
+<% transform_extra_prefixes = "moz:layout.css.prefixes.transforms webkit" %>
+
 ${helpers.predefined_type("transform", "Transform",
                           "generics::transform::Transform::none()",
-                          extra_prefixes="webkit moz",
+                          extra_prefixes=transform_extra_prefixes,
                           animation_value_type="ComputedValue",
                           gecko_ffi_name="mSpecifiedTransform",
                           flags="CREATES_STACKING_CONTEXT FIXPOS_CB",
@@ -517,7 +523,7 @@ ${helpers.predefined_type(
     "computed::Perspective::none()",
     gecko_ffi_name="mChildPerspective",
     spec="https://drafts.csswg.org/css-transforms/#perspective",
-    extra_prefixes="moz webkit",
+    extra_prefixes=transform_extra_prefixes,
     flags="CREATES_STACKING_CONTEXT FIXPOS_CB",
     animation_value_type="AnimatedPerspective",
     servo_restyle_damage = "reflow_out_of_flow",
@@ -527,15 +533,15 @@ ${helpers.predefined_type("perspective-origin",
                           "position::Position",
                           "computed::position::Position::center()",
                           boxed=True,
-                          extra_prefixes="moz webkit",
+                          extra_prefixes=transform_extra_prefixes,
                           spec="https://drafts.csswg.org/css-transforms-2/#perspective-origin-property",
                           animation_value_type="ComputedValue",
                           servo_restyle_damage = "reflow_out_of_flow")}
 
 ${helpers.single_keyword("backface-visibility",
                          "visible hidden",
                          spec="https://drafts.csswg.org/css-transforms/#backface-visibility-property",
-                         extra_prefixes="moz webkit",
+                         extra_prefixes=transform_extra_prefixes,
                          animation_value_type="discrete")}
 
 ${helpers.single_keyword("transform-box",
@@ -553,7 +559,7 @@ ${helpers.predefined_type(
     "computed::TransformStyle::" + ("Auto" if product == "servo" else "Flat"),
     spec="https://drafts.csswg.org/css-transforms-2/#transform-style-property",
     needs_context=False,
-    extra_prefixes="moz webkit",
+    extra_prefixes=transform_extra_prefixes,
     flags="CREATES_STACKING_CONTEXT FIXPOS_CB",
     animation_value_type="discrete",
     servo_restyle_damage = "reflow_out_of_flow",
@@ -563,7 +569,7 @@ ${helpers.predefined_type("transform-origin",
                           "TransformOrigin",
                           "computed::TransformOrigin::initial_value()",
                           animation_value_type="ComputedValue",
-                          extra_prefixes="moz webkit",
+                          extra_prefixes=transform_extra_prefixes,
                           gecko_ffi_name="mTransformOrigin",
                           boxed=True,
                           spec="https://drafts.csswg.org/css-transforms/#transform-origin-property",

components/style/properties/longhand/column.mako.rs

@@ -73,7 +73,7 @@ ${helpers.single_keyword("column-span", "none all",
                          products="gecko", animation_value_type="discrete",
                          gecko_pref="layout.css.column-span.enabled",
                          spec="https://drafts.csswg.org/css-multicol/#propdef-column-span",
-                         extra_prefixes="moz")}
+                         extra_prefixes="moz:layout.css.column-span.enabled")}
 
 ${helpers.single_keyword("column-rule-style",
                          "none hidden dotted dashed solid double groove ridge inset outset",

components/style/properties/longhand/font.mako.rs

@@ -150,7 +150,7 @@ ${helpers.predefined_type("font-feature-settings",
                           products="gecko",
                           initial_value="computed::FontFeatureSettings::normal()",
                           initial_specified_value="specified::FontFeatureSettings::normal()",
-                          extra_prefixes="moz",
+                          extra_prefixes="moz:layout.css.prefixes.font-features",
                           animation_value_type="discrete",
                           flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
                           spec="https://drafts.csswg.org/css-fonts/#propdef-font-feature-settings")}
@@ -178,7 +178,7 @@ ${helpers.predefined_type("font-language-override",
                           initial_value="computed::FontLanguageOverride::zero()",
                           initial_specified_value="specified::FontLanguageOverride::normal()",
                           animation_value_type="discrete",
-                          extra_prefixes="moz",
+                          extra_prefixes="moz:layout.css.prefixes.font-features",
                           flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
                           spec="https://drafts.csswg.org/css-fonts-3/#propdef-font-language-override")}
 

components/style/properties/longhand/position.mako.rs

@@ -57,12 +57,14 @@ ${helpers.predefined_type(
 // Flex container properties
 ${helpers.single_keyword("flex-direction", "row row-reverse column column-reverse",
                          spec="https://drafts.csswg.org/css-flexbox/#flex-direction-property",
-                         extra_prefixes="webkit", animation_value_type="discrete",
+                         extra_prefixes="webkit",
+                         animation_value_type="discrete",
                          servo_restyle_damage = "reflow")}
 
 ${helpers.single_keyword("flex-wrap", "nowrap wrap wrap-reverse",
                          spec="https://drafts.csswg.org/css-flexbox/#flex-wrap-property",
-                         extra_prefixes="webkit", animation_value_type="discrete",
+                         extra_prefixes="webkit",
+                         animation_value_type="discrete",
                          servo_restyle_damage = "reflow")}
 
 % if product == "servo":
@@ -267,7 +269,7 @@ ${helpers.predefined_type(
 
 ${helpers.single_keyword("box-sizing",
                          "content-box border-box",
-                         extra_prefixes="moz webkit",
+                         extra_prefixes="moz:layout.css.prefixes.box-sizing webkit",
                          spec="https://drafts.csswg.org/css-ui/#propdef-box-sizing",
                          gecko_enum_prefix="StyleBoxSizing",
                          custom_consts={ "content-box": "Content", "border-box": "Border" },

components/style/properties/shorthand/border.mako.rs

@@ -246,7 +246,8 @@ pub fn parse_border<'i, 't>(
 
 <%helpers:shorthand name="border-image" sub_properties="border-image-outset
     border-image-repeat border-image-slice border-image-source border-image-width"
-    extra_prefixes="moz webkit" spec="https://drafts.csswg.org/css-backgrounds-3/#border-image">
+    extra_prefixes="moz:layout.css.prefixes.border-image webkit"
+    spec="https://drafts.csswg.org/css-backgrounds-3/#border-image">
     use properties::longhands::{border_image_outset, border_image_repeat, border_image_slice};
     use properties::longhands::{border_image_source, border_image_width};
 

components/style/properties/shorthand/box.mako.rs

@@ -117,7 +117,8 @@ macro_rules! try_parse_one {
     };
 }
 
-<%helpers:shorthand name="transition" extra_prefixes="moz webkit"
+<%helpers:shorthand name="transition"
+                    extra_prefixes="moz:layout.css.prefixes.transitions webkit"
                     sub_properties="transition-property transition-duration
                                     transition-timing-function
                                     transition-delay"
@@ -257,7 +258,8 @@ macro_rules! try_parse_one {
     }
 </%helpers:shorthand>
 
-<%helpers:shorthand name="animation" extra_prefixes="moz webkit"
+<%helpers:shorthand name="animation"
+                    extra_prefixes="moz:layout.css.prefixes.animations webkit"
                     sub_properties="animation-name animation-duration
                                     animation-timing-function animation-delay
                                     animation-iteration-count animation-direction