Move `*_traits` and other shared types to `shared`

This is the start of the organization of types that are in their own
crates in order to break dependency cycles between other crates. The
idea here is that putting these packages into their own directory is the
first step toward cleaning them up. They have grown organically and it
is difficult to explain to new folks where to put new shared types. Many
of these crates contain more than traits or don't contain traits at all.

Notably, `script_traits` isn't touched because it is vendored from
Gecko. Eventually this will move to `third_party`.

1 files changed, 75 insertions, 0 deletions

diff --git a/components/shared/script_layout/rpc.rs b/components/shared/script_layout/rpc.rs
new file mode 100644
index 00000000000..3778d8f975a
--- /dev/null
+++ b/components/shared/script_layout/rpc.rs
@@ -0,0 +1,75 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use app_units::Au;
+use euclid::default::Rect;
+use euclid::Size2D;
+use script_traits::UntrustedNodeAddress;
+use servo_arc::Arc;
+use style::properties::style_structs::Font;
+use style_traits::CSSPixel;
+use webrender_api::ExternalScrollId;
+
+/// Synchronous messages that script can send to layout.
+///
+/// In general, you should use messages to talk to Layout. Use the RPC interface
+/// if and only if the work is
+///
+///   1) read-only with respect to LayoutThreadData,
+///   2) small,
+///   3) and really needs to be fast.
+pub trait LayoutRPC {
+    /// Requests the dimensions of the content box, as in the `getBoundingClientRect()` call.
+    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 scroll geometry of this node. Used by APIs such as `scrollTop`.
+    fn scrolling_area(&self) -> NodeGeometryResponse;
+    /// Requests the scroll id of this node. Used by APIs such as `scrollTop`
+    fn node_scroll_id(&self) -> NodeScrollIdResponse;
+    /// Query layout for the resolved value of a given CSS property
+    fn resolved_style(&self) -> ResolvedStyleResponse;
+    /// Query layout to get the resolved font style for canvas.
+    fn resolved_font_style(&self) -> Option<Arc<Font>>;
+    fn offset_parent(&self) -> OffsetParentResponse;
+    fn text_index(&self) -> TextIndexResponse;
+    /// Requests the list of nodes from the given point.
+    fn nodes_from_point_response(&self) -> Vec<UntrustedNodeAddress>;
+    /// Query layout to get the inner text for a given element.
+    fn element_inner_text(&self) -> String;
+    /// Get the dimensions of an iframe's inner window.
+    fn inner_window_dimensions(&self) -> Option<Size2D<f32, CSSPixel>>;
+}
+
+pub struct ContentBoxResponse(pub Option<Rect<Au>>);
+
+pub struct ContentBoxesResponse(pub Vec<Rect<Au>>);
+
+pub struct NodeGeometryResponse {
+    pub client_rect: Rect<i32>,
+}
+
+pub struct NodeScrollIdResponse(pub ExternalScrollId);
+
+pub struct ResolvedStyleResponse(pub String);
+
+#[derive(Clone)]
+pub struct OffsetParentResponse {
+    pub node_address: Option<UntrustedNodeAddress>,
+    pub rect: Rect<Au>,
+}
+
+impl OffsetParentResponse {
+    pub fn empty() -> OffsetParentResponse {
+        OffsetParentResponse {
+            node_address: None,
+            rect: Rect::zero(),
+        }
+    }
+}
+
+#[derive(Clone)]
+pub struct TextIndexResponse(pub Option<usize>);