Auto merge of #13589 - splav:SVGElement#12974, r=pcwalton,Ms2ger

Support SVG element

<!-- Please describe your changes on the following line: -->
minimal SVG element implementation
---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12974 (github issue number if applicable).

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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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2 files changed, 9 insertions, 0 deletions

diff --git a/components/script_layout_interface/lib.rs b/components/script_layout_interface/lib.rs
index cad2e012c7c..18c4805a485 100644
--- a/components/script_layout_interface/lib.rs
+++ b/components/script_layout_interface/lib.rs
@@ -95,6 +95,7 @@ pub enum LayoutElementType {
     HTMLTableRowElement,
     HTMLTableSectionElement,
     HTMLTextAreaElement,
+    SVGSVGElement,
 }
 
 pub struct HTMLCanvasData {
@@ -103,6 +104,11 @@ pub struct HTMLCanvasData {
     pub height: u32,
 }
 
+pub struct SVGSVGData {
+    pub width: u32,
+    pub height: u32,
+}
+
 /// The address of a node known to be valid. These are sent from script to layout.
 #[derive(Clone, PartialEq, Eq, Copy)]
 pub struct TrustedNodeAddress(pub *const c_void);
diff --git a/components/script_layout_interface/wrapper_traits.rs b/components/script_layout_interface/wrapper_traits.rs
index c02d76a2f4e..c98afa3a72e 100644
--- a/components/script_layout_interface/wrapper_traits.rs
+++ b/components/script_layout_interface/wrapper_traits.rs
@@ -5,6 +5,7 @@
 use HTMLCanvasData;
 use LayoutNodeType;
 use OpaqueStyleAndLayoutData;
+use SVGSVGData;
 use gfx_traits::{ByteIndex, LayerId, LayerType};
 use msg::constellation_msg::PipelineId;
 use range::Range;
@@ -362,6 +363,8 @@ pub trait ThreadSafeLayoutNode: Clone + Copy + NodeInfo + PartialEq + Sized {
 
     fn canvas_data(&self) -> Option<HTMLCanvasData>;
 
+    fn svg_data(&self) -> Option<SVGSVGData>;
+
     /// If this node is an iframe element, returns its pipeline ID. If this node is
     /// not an iframe element, fails.
     fn iframe_pipeline_id(&self) -> PipelineId;