Auto merge of #14367 - mrobinson:scroll-fragment-point, r=pcwalton

Reimplement scrolling to fragments

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #13736, #10753 (github issue number if applicable).

<!-- Either: -->
- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

This reimplemntation of the feature uses ScrollRootIds to scroll
particular scrollable areas of the page.

Fixes #13736.
Fixes #10753.

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/14367)
<!-- Reviewable:end -->

1 files changed, 2 insertions, 1 deletions

diff --git a/components/script_traits/script_msg.rs b/components/script_traits/script_msg.rs
index 7ef20af9fbc..e91a034fec9 100644
--- a/components/script_traits/script_msg.rs
+++ b/components/script_traits/script_msg.rs
@@ -16,6 +16,7 @@ use canvas_traits::CanvasMsg;
 use devtools_traits::{ScriptToDevtoolsControlMsg, WorkerId};
 use euclid::point::Point2D;
 use euclid::size::Size2D;
+use gfx_traits::ScrollRootId;
 use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::{FrameId, PipelineId, TraversalDirection};
 use msg::constellation_msg::{Key, KeyModifiers, KeyState};
@@ -121,7 +122,7 @@ pub enum ScriptMsg {
     /// Check if an alert dialog box should be presented
     Alert(PipelineId, String, IpcSender<bool>),
     /// Scroll a page in a window
-    ScrollFragmentPoint(PipelineId, Point2D<f32>, bool),
+    ScrollFragmentPoint(PipelineId, ScrollRootId, Point2D<f32>, bool),
     /// Set title of current page
     /// https://html.spec.whatwg.org/multipage/#document.title
     SetTitle(PipelineId, Option<String>),