chore: Clean up use of `gfx` and `constellation` types (#31981)

This change contains three semi-related clean ups:

1. the `to_webrender()` and `from_webrender()` functions on Pipeline are
   turned into more-idiomatic `From` and `Into` implementations.
2. `combine_id_with_fragment_type` now returns a `u64` as that is what is
   expected for all callers and not a `usize`.
3. The `query_scroll_id` query is removed entirely. The
   `ExternalScrollId` that this queries is easily generated directly
   from the node's opaque id. Querying into layout isn't necessary at
   all.

1 files changed, 1 insertions, 2 deletions

diff --git a/components/shared/script_layout/lib.rs b/components/shared/script_layout/lib.rs
index 3279f993820..20d8c982dc2 100644
--- a/components/shared/script_layout/lib.rs
+++ b/components/shared/script_layout/lib.rs
@@ -46,7 +46,7 @@ use style::properties::PropertyId;
 use style::selector_parser::PseudoElement;
 use style::stylesheets::Stylesheet;
 use style_traits::CSSPixel;
-use webrender_api::{ExternalScrollId, ImageKey};
+use webrender_api::ImageKey;
 
 pub type GenericLayoutData = dyn Any + Send + Sync;
 
@@ -235,7 +235,6 @@ pub trait Layout {
         animations: DocumentAnimationSet,
         animation_timeline_value: f64,
     ) -> Option<ServoArc<Font>>;
-    fn query_scroll_id(&self, node: TrustedNodeAddress) -> ExternalScrollId;
     fn query_scrolling_area(&self, node: Option<OpaqueNode>) -> Rect<i32>;
     fn query_text_indext(&self, node: OpaqueNode, point: Point2D<f32>) -> Option<usize>;
 }