Auto merge of #6662 - tschneidereit:client-geometry, r=glennw,pcwatson

Implement Element.client{Top,Left,Width,Height}

This isn't done, but contains a working implementation of at least `clientTop`. Feedback would be much appreciated: it's probably far from ideal.

Implementing `clientLeft` is straight-forward, I think, but `clientWidth` and `clientHeight` require accessing the `border_box` - and I don't know how that works, yet.

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1 files changed, 6 insertions, 0 deletions

diff --git a/components/script/layout_interface.rs b/components/script/layout_interface.rs
index b94758f56b7..d94f6e4a581 100644
--- a/components/script/layout_interface.rs
+++ b/components/script/layout_interface.rs
@@ -95,6 +95,8 @@ pub trait LayoutRPC {
     fn content_box(&self) -> ContentBoxResponse;
     /// Requests the dimensions of all the content boxes, as in the `getClientRects()` call.
     fn content_boxes(&self) -> ContentBoxesResponse;
+    /// Requests the geometry of this node. Used by APIs such as `clientTop`.
+    fn node_geometry(&self) -> NodeGeometryResponse;
     /// Requests the node containing the point of interest
     fn hit_test(&self, node: TrustedNodeAddress, point: Point2D<f32>) -> Result<HitTestResponse, ()>;
     fn mouse_over(&self, node: TrustedNodeAddress, point: Point2D<f32>) -> Result<MouseOverResponse, ()>;
@@ -102,6 +104,9 @@ pub trait LayoutRPC {
 
 pub struct ContentBoxResponse(pub Rect<Au>);
 pub struct ContentBoxesResponse(pub Vec<Rect<Au>>);
+pub struct NodeGeometryResponse {
+    pub client_rect: Rect<i32>,
+}
 pub struct HitTestResponse(pub UntrustedNodeAddress);
 pub struct MouseOverResponse(pub Vec<UntrustedNodeAddress>);
 
@@ -120,6 +125,7 @@ pub enum ReflowQueryType {
     NoQuery,
     ContentBoxQuery(TrustedNodeAddress),
     ContentBoxesQuery(TrustedNodeAddress),
+    NodeGeometryQuery(TrustedNodeAddress),
 }
 
 /// Information needed for a reflow.