style: Turn the CSS flexible box model on by default.

See
https://groups.google.com/forum/#!topic/mozilla.dev.servo/MWBms2_BMJo
for discussion.

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

@@ -23,7 +23,6 @@
         """.split()
         if product == "gecko":
             values += "-moz-box -moz-inline-box".split()
-        experimental_values = set("flex".split())
     %>
     pub use self::computed_value::T as SpecifiedValue;
     use values::computed::ComputedValueAsSpecified;
@@ -61,12 +60,6 @@
         match_ignore_ascii_case! { try!(input.expect_ident()),
             % for value in values:
                 "${value}" => {
-                    % if value in experimental_values and product == "servo":
-                        if !::util::prefs::PREFS.get("layout.${value}.enabled")
-                            .as_boolean().unwrap_or(false) {
-                            return Err(())
-                        }
-                    % endif
                     Ok(computed_value::T::${to_rust_ident(value)})
                 },
             % endfor

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

@@ -66,45 +66,41 @@
 
 // Flex container properties
 ${helpers.single_keyword("flex-direction", "row row-reverse column column-reverse",
-                         experimental=True, animatable=False)}
+                         animatable=False)}
 
 ${helpers.single_keyword("flex-wrap", "nowrap wrap wrap-reverse",
-                         experimental=True, animatable=False)}
+                         animatable=False)}
 
 // FIXME(stshine): The type of 'justify-content' and 'align-content' is uint16_t in gecko
 // FIXME(stshine): Its higher bytes are used to store fallback value. Disable them in geckolib for now
 ${helpers.single_keyword("justify-content", "flex-start flex-end center space-between space-around",
-                         experimental=True,
                          gecko_constant_prefix="NS_STYLE_JUSTIFY",
                          products="servo",
                          animatable=False)}
 
 // FIXME(heycam): Disable align-items in geckolib since we don't support the Gecko initial value
 // 'normal' yet.
 ${helpers.single_keyword("align-items", "stretch flex-start flex-end center baseline",
-                         experimental=True,
                          need_clone=True,
                          gecko_constant_prefix="NS_STYLE_ALIGN",
                          animatable=False,
                          products="servo")}
 
 ${helpers.single_keyword("align-content", "stretch flex-start flex-end center space-between space-around",
-                         experimental=True,
                          gecko_constant_prefix="NS_STYLE_ALIGN",
                          products="servo",
                          animatable=False)}
 
 // Flex item properties
 ${helpers.predefined_type("flex-grow", "Number",
                           "0.0", "parse_non_negative",
-                          experimental=True, animatable=True)}
+                          animatable=True)}
 
 ${helpers.predefined_type("flex-shrink", "Number",
                           "1.0", "parse_non_negative",
-                          experimental=True, animatable=True)}
+                          animatable=True)}
 
 ${helpers.single_keyword("align-self", "auto stretch flex-start flex-end center baseline",
-                         experimental=True,
                          need_clone=True,
                          gecko_constant_prefix="NS_STYLE_ALIGN",
                          animatable=False)}

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

@@ -5,8 +5,7 @@
 <%namespace name="helpers" file="/helpers.mako.rs" />
 
 // https://drafts.csswg.org/css-flexbox/#flex-flow-property
-<%helpers:shorthand name="flex-flow" sub_properties="flex-direction flex-wrap"
-                                     experimental="True">
+<%helpers:shorthand name="flex-flow" sub_properties="flex-direction flex-wrap">
     use properties::longhands::{flex_direction, flex_wrap};
 
     pub fn parse_value(context: &ParserContext, input: &mut Parser) -> Result<Longhands, ()> {
@@ -56,8 +55,7 @@
 </%helpers:shorthand>
 
 // https://drafts.csswg.org/css-flexbox/#flex-property
-<%helpers:shorthand name="flex" sub_properties="flex-grow flex-shrink flex-basis"
-                                experimental="True">
+<%helpers:shorthand name="flex" sub_properties="flex-grow flex-shrink flex-basis">
     use app_units::Au;
     use values::specified::{Number, Length, LengthOrPercentageOrAutoOrContent};
 

resources/package-prefs.json

@@ -49,8 +49,6 @@
   "layout.column-gap.enabled": false,
   "layout.column-width.enabled": false,
   "layout.columns.enabled": false,
-  "layout.flex-direction.enabled": false,
-  "layout.flex.enabled": false,
   "layout.text-orientation.enabled": false,
   "layout.viewport.enabled": false,
   "layout.writing-mode.enabled": false,

resources/prefs.json

@@ -50,8 +50,6 @@
   "layout.column-gap.enabled": false,
   "layout.column-width.enabled": false,
   "layout.columns.enabled": false,
-  "layout.flex-direction.enabled": false,
-  "layout.flex.enabled": false,
   "layout.text-orientation.enabled": false,
   "layout.viewport.enabled": false,
   "layout.writing-mode.enabled": false,