Auto merge of #19023 - emilio:remove-pres-hints-trait, r=KiChjang

style: Remove PresentationalHintsSynthesizer.

This is not really an useful abstraction, and I never knew how to spell it.

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components/layout_thread/dom_wrapper.rs

@@ -69,7 +69,7 @@ use style::computed_values::display;
 use style::context::SharedStyleContext;
 use style::data::ElementData;
 use style::dom::{DomChildren, LayoutIterator, NodeInfo, OpaqueNode};
-use style::dom::{PresentationalHintsSynthesizer, TElement, TNode};
+use style::dom::{TElement, TNode};
 use style::element_state::*;
 use style::font_metrics::ServoMetricsProvider;
 use style::properties::{ComputedValues, PropertyDeclarationBlock};
@@ -338,18 +338,6 @@ impl<'le> fmt::Debug for ServoLayoutElement<'le> {
     }
 }
 
-impl<'le> PresentationalHintsSynthesizer for ServoLayoutElement<'le> {
-    fn synthesize_presentational_hints_for_legacy_attributes<V>(&self,
-                                                                _visited_handling: VisitedHandlingMode,
-                                                                hints: &mut V)
-        where V: Push<ApplicableDeclarationBlock>
-    {
-        unsafe {
-            self.element.synthesize_presentational_hints_for_legacy_attributes(hints);
-        }
-    }
-}
-
 impl<'le> TElement for ServoLayoutElement<'le> {
     type ConcreteNode = ServoLayoutNode<'le>;
     type TraversalChildrenIterator = DomChildren<Self::ConcreteNode>;
@@ -520,6 +508,19 @@ impl<'le> TElement for ServoLayoutElement<'le> {
         // FIXME(emilio): We should be able to give the right answer though!
         false
     }
+
+    fn synthesize_presentational_hints_for_legacy_attributes<V>(
+        &self,
+        _visited_handling: VisitedHandlingMode,
+        hints: &mut V,
+    )
+    where
+        V: Push<ApplicableDeclarationBlock>,
+    {
+        unsafe {
+            self.element.synthesize_presentational_hints_for_legacy_attributes(hints);
+        }
+    }
 }
 
 impl<'le> PartialEq for ServoLayoutElement<'le> {
@@ -1245,10 +1246,3 @@ impl<'le> ::selectors::Element for ServoThreadSafeLayoutElement<'le> {
         false
     }
 }
-
-impl<'le> PresentationalHintsSynthesizer for ServoThreadSafeLayoutElement<'le> {
-    fn synthesize_presentational_hints_for_legacy_attributes<V>(&self,
-                                                                _visited_handling: VisitedHandlingMode,
-                                                                _hints: &mut V)
-        where V: Push<ApplicableDeclarationBlock> {}
-}

components/script_layout_interface/wrapper_traits.rs

@@ -20,7 +20,7 @@ use style::attr::AttrValue;
 use style::computed_values::display;
 use style::context::SharedStyleContext;
 use style::data::ElementData;
-use style::dom::{LayoutIterator, NodeInfo, PresentationalHintsSynthesizer, TNode};
+use style::dom::{LayoutIterator, NodeInfo, TNode};
 use style::dom::OpaqueNode;
 use style::font_metrics::ServoMetricsProvider;
 use style::properties::{CascadeFlags, ComputedValues};
@@ -290,10 +290,14 @@ pub trait DangerousThreadSafeLayoutNode: ThreadSafeLayoutNode {
     unsafe fn dangerous_next_sibling(&self) -> Option<Self>;
 }
 
-pub trait ThreadSafeLayoutElement: Clone + Copy + Sized + Debug +
-                                   ::selectors::Element<Impl=SelectorImpl> +
-                                   GetLayoutData +
-                                   PresentationalHintsSynthesizer {
+pub trait ThreadSafeLayoutElement
+    : Clone
+    + Copy
+    + Sized
+    + Debug
+    + ::selectors::Element<Impl=SelectorImpl>
+    + GetLayoutData
+{
     type ConcreteThreadSafeLayoutNode: ThreadSafeLayoutNode<ConcreteThreadSafeLayoutElement = Self>;
 
     fn as_node(&self) -> Self::ConcreteThreadSafeLayoutNode;

components/style/dom.rs

@@ -311,16 +311,6 @@ fn fmt_subtree<F, N: TNode>(f: &mut fmt::Formatter, stringify: &F, n: N, indent:
     Ok(())
 }
 
-/// A trait used to synthesize presentational hints for HTML element attributes.
-pub trait PresentationalHintsSynthesizer {
-    /// Generate the proper applicable declarations due to presentational hints,
-    /// and insert them into `hints`.
-    fn synthesize_presentational_hints_for_legacy_attributes<V>(&self,
-                                                                visited_handling: VisitedHandlingMode,
-                                                                hints: &mut V)
-        where V: Push<ApplicableDeclarationBlock>;
-}
-
 /// The element trait, the main abstraction the style crate acts over.
 pub trait TElement
     : Eq
@@ -331,7 +321,6 @@ pub trait TElement
     + Copy
     + Clone
     + SelectorsElement<Impl = SelectorImpl>
-    + PresentationalHintsSynthesizer
 {
     /// The concrete node type.
     type ConcreteNode: TNode<ConcreteElement = Self>;
@@ -808,6 +797,16 @@ pub trait TElement
     /// Returns whether this element is the main body element of the HTML
     /// document it is on.
     fn is_html_document_body_element(&self) -> bool;
+
+    /// Generate the proper applicable declarations due to presentational hints,
+    /// and insert them into `hints`.
+    fn synthesize_presentational_hints_for_legacy_attributes<V>(
+        &self,
+        visited_handling: VisitedHandlingMode,
+        hints: &mut V,
+    )
+    where
+        V: Push<ApplicableDeclarationBlock>;
 }
 
 /// TNode and TElement aren't Send because we want to be careful and explicit

components/style/gecko/wrapper.rs

@@ -20,8 +20,7 @@ use applicable_declarations::ApplicableDeclarationBlock;
 use atomic_refcell::{AtomicRefCell, AtomicRef, AtomicRefMut};
 use context::{QuirksMode, SharedStyleContext, PostAnimationTasks, UpdateAnimationsTasks};
 use data::ElementData;
-use dom::{LayoutIterator, NodeInfo, TElement, TNode};
-use dom::{OpaqueNode, PresentationalHintsSynthesizer};
+use dom::{LayoutIterator, NodeInfo, OpaqueNode, TElement, TNode};
 use element_state::{ElementState, DocumentState, NS_DOCUMENT_STATE_WINDOW_INACTIVE};
 use error_reporting::ParseErrorReporter;
 use font_metrics::{FontMetrics, FontMetricsProvider, FontMetricsQueryResult};
@@ -1526,23 +1525,7 @@ impl<'le> TElement for GeckoElement<'le> {
 
         unsafe { bindings::Gecko_IsDocumentBody(self.0) }
     }
-}
 
-impl<'le> PartialEq for GeckoElement<'le> {
-    fn eq(&self, other: &Self) -> bool {
-        self.0 as *const _ == other.0 as *const _
-    }
-}
-
-impl<'le> Eq for GeckoElement<'le> {}
-
-impl<'le> Hash for GeckoElement<'le> {
-    fn hash<H: Hasher>(&self, state: &mut H) {
-        (self.0 as *const _).hash(state);
-    }
-}
-
-impl<'le> PresentationalHintsSynthesizer for GeckoElement<'le> {
     fn synthesize_presentational_hints_for_legacy_attributes<V>(
         &self,
         visited_handling: VisitedHandlingMode,
@@ -1690,6 +1673,20 @@ impl<'le> PresentationalHintsSynthesizer for GeckoElement<'le> {
     }
 }
 
+impl<'le> PartialEq for GeckoElement<'le> {
+    fn eq(&self, other: &Self) -> bool {
+        self.0 as *const _ == other.0 as *const _
+    }
+}
+
+impl<'le> Eq for GeckoElement<'le> {}
+
+impl<'le> Hash for GeckoElement<'le> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        (self.0 as *const _).hash(state);
+    }
+}
+
 impl<'le> ::selectors::Element for GeckoElement<'le> {
     type Impl = SelectorImpl;