servo: Merge #19431 - Add picture element (from Rakhisharma:picture_element); r=jdm

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes are part of #11416  (github issue number if applicable).

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- [ ] There are tests for these changes OR
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Source-Repo: https://github.com/servo/servo
Source-Revision: 76b4e5cefb68e64a1bb2df78b32b05eba41eb678

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 7664270a6782da37f1b8659101ee4cbd00093741

servo/components/script/dom/create.rs

@@ -54,6 +54,7 @@ use dom::htmloptionelement::HTMLOptionElement;
 use dom::htmloutputelement::HTMLOutputElement;
 use dom::htmlparagraphelement::HTMLParagraphElement;
 use dom::htmlparamelement::HTMLParamElement;
+use dom::htmlpictureelement::HTMLPictureElement;
 use dom::htmlpreelement::HTMLPreElement;
 use dom::htmlprogresselement::HTMLProgressElement;
 use dom::htmlquoteelement::HTMLQuoteElement;
@@ -309,6 +310,7 @@ pub fn create_native_html_element(
         local_name!("output")     => make!(HTMLOutputElement),
         local_name!("p")          => make!(HTMLParagraphElement),
         local_name!("param")      => make!(HTMLParamElement),
+        local_name!("picture")    => make!(HTMLPictureElement),
         local_name!("plaintext")  => make!(HTMLPreElement),
         local_name!("pre")        => make!(HTMLPreElement),
         local_name!("progress")   => make!(HTMLProgressElement),

servo/components/script/dom/htmlpictureelement.rs

@@ -0,0 +1,36 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+use dom::bindings::codegen::Bindings::HTMLPictureElementBinding;
+use dom::bindings::root::DomRoot;
+use dom::document::Document;
+use dom::htmlelement::HTMLElement;
+use dom::node::Node;
+use dom_struct::dom_struct;
+use html5ever::{LocalName, Prefix};
+
+#[dom_struct]
+pub struct HTMLPictureElement {
+    htmlelement: HTMLElement,
+}
+
+impl HTMLPictureElement {
+    fn new_inherited(local_name: LocalName,
+                     prefix: Option<Prefix>,
+                     document: &Document) -> HTMLPictureElement {
+        HTMLPictureElement {
+            htmlelement:
+                HTMLElement::new_inherited(local_name, prefix, document)
+        }
+    }
+
+    #[allow(unrooted_must_root)]
+    pub fn new(local_name: LocalName,
+               prefix: Option<Prefix>,
+               document: &Document) -> DomRoot<HTMLPictureElement> {
+        Node::reflect_node(Box::new(HTMLPictureElement::new_inherited(local_name, prefix, document)),
+                           document,
+                           HTMLPictureElementBinding::Wrap)
+    }
+}

servo/components/script/dom/mod.rs

@@ -348,6 +348,7 @@ pub mod htmloptionscollection;
 pub mod htmloutputelement;
 pub mod htmlparagraphelement;
 pub mod htmlparamelement;
+pub mod htmlpictureelement;
 pub mod htmlpreelement;
 pub mod htmlprogresselement;
 pub mod htmlquoteelement;

servo/components/script/dom/webidls/HTMLPictureElement.webidl

@@ -0,0 +1,7 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#htmlpictureelement
+[HTMLConstructor]
+interface HTMLPictureElement : HTMLElement {};