Bug 1404140 - Remove the GetCSNeedsLayoutFlush flag, as it is unneeded now. r=heycam

MANUAL PUSH: Would need to reorder the stack manually (https://bugzilla.mozilla.org/show_bug.cgi?id=1481539)

Differential Revision: https://phabricator.services.mozilla.com/D40300

layout/style/CSSPropFlags.h

@@ -16,10 +16,6 @@ enum class CSSPropFlags : uint8_t {
   // attribute mapping.
   Inaccessible = 1 << 0,
 
-  // This property's getComputedStyle implementation requires layout to
-  // be flushed.
-  GetCSNeedsLayoutFlush = 1 << 1,
-
   // The following two flags along with the pref defines where the this
   // property can be used:
   // * If none of the two flags is presented, the pref completely controls
@@ -36,24 +32,24 @@ enum class CSSPropFlags : uint8_t {
   // transitions) these flags are ignored. That is, if the property is disabled
   // by a pref, we will *not* run animations or transitions on it even in
   // UA sheets or chrome.
-  EnabledInUASheets = 1 << 2,
+  EnabledInUASheets = 1 << 1,
-  EnabledInChrome = 1 << 3,
+  EnabledInChrome = 1 << 2,
   EnabledInUASheetsAndChrome = EnabledInUASheets | EnabledInChrome,
   EnabledMask = EnabledInUASheetsAndChrome,
 
   // This property can be animated on the compositor.
-  CanAnimateOnCompositor = 1 << 4,
+  CanAnimateOnCompositor = 1 << 3,
 
   // This property is an internal property that is not represented in
   // the DOM. Properties with this flag are defined in an #ifndef
   // CSS_PROP_LIST_EXCLUDE_INTERNAL section.
-  Internal = 1 << 5,
+  Internal = 1 << 4,
 
   // Whether this property should be serialized by Servo in getComputedStyle.
-  SerializedByServo = 1 << 6,
+  SerializedByServo = 1 << 5,
 
   // Whether this is a logical property.
-  IsLogical = 1 << 7,
+  IsLogical = 1 << 6,
 };
 
 MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(CSSPropFlags)

layout/style/ServoCSSPropList.mako.py

@@ -69,23 +69,42 @@ LONGHANDS_NOT_SERIALIZED_WITH_SERVO = [
     "column-rule-width",
 
     # These resolve auto to zero in a few cases, but not all.
-    "max-block-size",
     "max-height",
-    "max-inline-size",
     "max-width",
-    "min-block-size",
     "min-height",
-    "min-inline-size",
     "min-width",
 
     # resistfingerprinting stuff.
     "-moz-osx-font-smoothing",
+
+    # Layout dependent.
+    "width",
+    "height",
+    "line-height",
+    "grid-template-rows",
+    "grid-template-columns",
+    "perspective-origin",
+    "transform-origin",
+    "transform",
+    "top",
+    "right",
+    "bottom",
+    "left",
+    "border-top-width",
+    "border-right-width",
+    "border-bottom-width",
+    "border-left-width",
+    "margin-top",
+    "margin-right",
+    "margin-bottom",
+    "margin-left",
+    "padding-top",
+    "padding-right",
+    "padding-bottom",
+    "padding-left",
 ]
 
 def serialized_by_servo(prop):
-    # If the property requires layout information, no such luck.
-    if "GETCS_NEEDS_LAYOUT_FLUSH" in prop.flags:
-        return False
     if prop.type() == "shorthand":
         # FIXME: Need to serialize a value interpolated with currentcolor
         # properly to be able to use text-decoration, and figure out what to do
@@ -114,8 +133,6 @@ def flags(prop):
         result.append("Internal")
     if prop.enabled_in == "":
         result.append("Inaccessible")
-    if "GETCS_NEEDS_LAYOUT_FLUSH" in prop.flags:
-        result.append("GetCSNeedsLayoutFlush")
     if "CAN_ANIMATE_ON_COMPOSITOR" in prop.flags:
         result.append("CanAnimateOnCompositor")
     if exposed_on_getcs(prop):

modules/libpref/init/StaticPrefList.yaml

@@ -4464,11 +4464,6 @@
 #
 # Only enabled on Nightly and early beta, at least for now.
 #
-# NOTE(emilio): If / when removing this pref, the GETCS_NEEDS_LAYOUT_FLUSH flag
-# should be removed from line-height (and we should let -moz-block-height
-# compute to the keyword as well, which shouldn't be observable anyway since
-# it's an internal value).
-#
 # It'd be nice to make numbers compute also to themselves, but it looks like
 # everybody agrees on turning them into pixels, see the discussion starting
 # from [1].

servo/components/style/properties/longhands/border.mako.rs

@@ -58,7 +58,6 @@
         animation_value_type="NonNegativeLength",
         logical=is_logical,
         logical_group="border-width",
-        flags="GETCS_NEEDS_LAYOUT_FLUSH",
         allow_quirks="No" if is_logical else "Yes",
         servo_restyle_damage="reflow rebuild_and_reflow_inline"
     )}

servo/components/style/properties/longhands/box.mako.rs

@@ -339,8 +339,7 @@ ${helpers.predefined_type(
     servo_2020_pref="layout.2020.unimplemented",
     extra_prefixes=transform_extra_prefixes,
     animation_value_type="ComputedValue",
-    flags="CREATES_STACKING_CONTEXT FIXPOS_CB \
+    flags="CREATES_STACKING_CONTEXT FIXPOS_CB CAN_ANIMATE_ON_COMPOSITOR",
-           GETCS_NEEDS_LAYOUT_FLUSH CAN_ANIMATE_ON_COMPOSITOR",
     spec="https://drafts.csswg.org/css-transforms/#propdef-transform",
     servo_restyle_damage="reflow_out_of_flow",
 )}
@@ -552,7 +551,6 @@ ${helpers.predefined_type(
     boxed=True,
     extra_prefixes=transform_extra_prefixes,
     spec="https://drafts.csswg.org/css-transforms-2/#perspective-origin-property",
-    flags="GETCS_NEEDS_LAYOUT_FLUSH",
     animation_value_type="ComputedValue",
     servo_restyle_damage="reflow_out_of_flow"
 )}
@@ -600,7 +598,6 @@ ${helpers.predefined_type(
     extra_prefixes=transform_extra_prefixes,
     gecko_ffi_name="mTransformOrigin",
     boxed=True,
-    flags="GETCS_NEEDS_LAYOUT_FLUSH",
     spec="https://drafts.csswg.org/css-transforms/#transform-origin-property",
     servo_restyle_damage="reflow_out_of_flow",
 )}

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

@@ -23,7 +23,6 @@ ${helpers.predefined_type(
     engines="gecko servo-2013 servo-2020",
     servo_2020_pref="layout.2020.unimplemented",
     animation_value_type="LineHeight",
-    flags="GETCS_NEEDS_LAYOUT_FLUSH",
     spec="https://drafts.csswg.org/css2/visudet.html#propdef-line-height",
     servo_restyle_damage="reflow"
 )}

servo/components/style/properties/longhands/margin.mako.rs

@@ -24,7 +24,6 @@
         logical=side[1],
         logical_group="margin",
         spec=spec,
-        flags="GETCS_NEEDS_LAYOUT_FLUSH",
         allowed_in_page_rule=True,
         servo_restyle_damage="reflow"
     )}

servo/components/style/properties/longhands/padding.mako.rs

@@ -23,7 +23,6 @@
         logical=side[1],
         logical_group="padding",
         spec=spec,
-        flags="GETCS_NEEDS_LAYOUT_FLUSH",
         allow_quirks="No" if side[1] else "Yes",
         servo_restyle_damage="reflow rebuild_and_reflow_inline"
     )}

servo/components/style/properties/longhands/position.mako.rs

@@ -17,7 +17,6 @@
         engines="gecko servo-2013 servo-2020",
         servo_2020_pref="layout.2020.unimplemented",
         spec="https://www.w3.org/TR/CSS2/visuren.html#propdef-%s" % side,
-        flags="GETCS_NEEDS_LAYOUT_FLUSH",
         animation_value_type="ComputedValue",
         allow_quirks="Yes",
         servo_restyle_damage="reflow_out_of_flow",
@@ -33,7 +32,6 @@
         engines="gecko servo-2013 servo-2020",
         servo_2020_pref="layout.2020.unimplemented",
         spec="https://drafts.csswg.org/css-logical-props/#propdef-inset-%s" % side,
-        flags="GETCS_NEEDS_LAYOUT_FLUSH",
         alias="offset-%s:layout.css.offset-logical-properties.enabled" % side,
         animation_value_type="ComputedValue",
         logical=True,
@@ -285,7 +283,6 @@ ${helpers.predefined_type(
         allow_quirks="No" if logical else "Yes",
         spec=spec % size,
         animation_value_type="Size",
-        flags="GETCS_NEEDS_LAYOUT_FLUSH",
         servo_restyle_damage="reflow",
     )}
     // min-width, min-height, min-block-size, min-inline-size
@@ -379,7 +376,6 @@ ${helpers.predefined_type(
         engines="gecko",
         spec="https://drafts.csswg.org/css-grid/#propdef-grid-template-%ss" % kind,
         boxed=True,
-        flags="GETCS_NEEDS_LAYOUT_FLUSH",
         animation_value_type="ComputedValue",
     )}
 

servo/components/style/properties/longhands/ui.mako.rs

@@ -80,7 +80,6 @@ ${helpers.predefined_type(
     "Transform",
     "generics::transform::Transform::none()",
     engines="gecko",
-    flags="GETCS_NEEDS_LAYOUT_FLUSH",
     animation_value_type="ComputedValue",
     spec="None (Nonstandard internal property)",
     enabled_in="chrome",
@@ -94,7 +93,6 @@ ${helpers.predefined_type(
     animation_value_type="ComputedValue",
     gecko_ffi_name="mWindowTransformOrigin",
     boxed=True,
-    flags="GETCS_NEEDS_LAYOUT_FLUSH",
     spec="None (Nonstandard internal property)",
     enabled_in="chrome",
 )}

servo/components/style/properties/properties.mako.rs

@@ -979,13 +979,10 @@ bitflags! {
         const APPLIES_TO_CUE = 1 << 6;
         /// This longhand property applies to ::marker.
         const APPLIES_TO_MARKER = 1 << 7;
-        /// This property's getComputedStyle implementation requires layout
-        /// to be flushed.
-        const GETCS_NEEDS_LAYOUT_FLUSH = 1 << 8;
         /// This property is a legacy shorthand.
         ///
         /// https://drafts.csswg.org/css-cascade/#legacy-shorthand
-        const IS_LEGACY_SHORTHAND = 1 << 9;
+        const IS_LEGACY_SHORTHAND = 1 << 8;
 
         /* The following flags are currently not used in Rust code, they
          * only need to be listed in corresponding properties so that

servo/ports/geckolib/glue.rs

@@ -6040,15 +6040,7 @@ pub unsafe extern "C" fn Servo_GetPropertyValue(
     prop: nsCSSPropertyID,
     value: *mut nsAString,
 ) {
-    use style::properties::PropertyFlags;
-
     if let Ok(longhand) = LonghandId::from_nscsspropertyid(prop) {
-        debug_assert!(
-            !longhand
-                .flags()
-                .contains(PropertyFlags::GETCS_NEEDS_LAYOUT_FLUSH),
-            "We're not supposed to serialize layout-dependent properties"
-        );
         style
             .get_longhand_property_value(longhand, &mut CssWriter::new(&mut *value))
             .unwrap();
@@ -6068,12 +6060,6 @@ pub unsafe extern "C" fn Servo_GetPropertyValue(
             "This won't quite do the right thing if we want to serialize \
              logical shorthands"
         );
-        debug_assert!(
-            !longhand
-                .flags()
-                .contains(PropertyFlags::GETCS_NEEDS_LAYOUT_FLUSH),
-            "Layout-dependent properties shouldn't get here"
-        );
         let animated = AnimationValue::from_computed_values(longhand, style).expect(
             "Somebody tried to serialize a shorthand with \
              non-animatable properties, would need more code \