Auto merge of #16712 - z1mvader:atomize_ns_prefix, r=SimonSapin

Changed all prefixes from DOMString to the atomic Prefix from html5ever

<!-- Please describe your changes on the following line: -->
I just changed the `prefix` parameters on the constructors of several HTML elements. The type now is `Option<Prefix>`. I also changed the sizes of the `sizeof.rs` unit test to match the new values.

---
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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 #16700  (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because it should not affect anything else

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components/script/dom/create.rs

@@ -3,7 +3,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use dom::bindings::js::Root;
-use dom::bindings::str::DOMString;
 use dom::document::Document;
 use dom::element::Element;
 use dom::element::ElementCreator;
@@ -77,11 +76,11 @@ use dom::htmlulistelement::HTMLUListElement;
 use dom::htmlunknownelement::HTMLUnknownElement;
 use dom::htmlvideoelement::HTMLVideoElement;
 use dom::svgsvgelement::SVGSVGElement;
-use html5ever::QualName;
+use html5ever::{QualName, Prefix};
 use servo_config::prefs::PREFS;
 
 fn create_svg_element(name: QualName,
-                      prefix: Option<DOMString>,
+                      prefix: Option<Prefix>,
                       document: &Document)
                       -> Root<Element> {
     assert!(name.ns == ns!(svg));
@@ -108,7 +107,7 @@ fn create_svg_element(name: QualName,
 }
 
 fn create_html_element(name: QualName,
-                      prefix: Option<DOMString>,
+                      prefix: Option<Prefix>,
                       document: &Document,
                       creator: ElementCreator)
                       -> Root<Element> {
@@ -277,10 +276,7 @@ pub fn create_element(name: QualName,
                       document: &Document,
                       creator: ElementCreator)
                       -> Root<Element> {
-    // FIXME(ajeffrey): Convert directly from Prefix to DOMString.
-
-    let prefix = name.prefix.as_ref().map(|p| DOMString::from(&**p));
-
+    let prefix = name.prefix.clone();
     match name.ns {
         ns!(html)   => create_html_element(name, prefix, document, creator),
         ns!(svg)    => create_svg_element(name, prefix, document),

components/script/dom/element.rs

@@ -123,7 +123,7 @@ pub struct Element {
     local_name: LocalName,
     tag_name: TagName,
     namespace: Namespace,
-    prefix: Option<DOMString>,
+    prefix: Option<Prefix>,
     attrs: DOMRefCell<Vec<JS<Attr>>>,
     id_attribute: DOMRefCell<Option<Atom>>,
     #[ignore_heap_size_of = "Arc"]
@@ -202,14 +202,14 @@ impl Element {
     }
 
     pub fn new_inherited(local_name: LocalName,
-                         namespace: Namespace, prefix: Option<DOMString>,
+                         namespace: Namespace, prefix: Option<Prefix>,
                          document: &Document) -> Element {
         Element::new_inherited_with_state(ElementState::empty(), local_name,
                                           namespace, prefix, document)
     }
 
     pub fn new_inherited_with_state(state: ElementState, local_name: LocalName,
-                                    namespace: Namespace, prefix: Option<DOMString>,
+                                    namespace: Namespace, prefix: Option<Prefix>,
                                     document: &Document)
                                     -> Element {
         Element {
@@ -230,7 +230,7 @@ impl Element {
 
     pub fn new(local_name: LocalName,
                namespace: Namespace,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<Element> {
         Node::reflect_node(
             box Element::new_inherited(local_name, namespace, prefix, document),
@@ -815,7 +815,7 @@ impl Element {
         &self.namespace
     }
 
-    pub fn prefix(&self) -> Option<&DOMString> {
+    pub fn prefix(&self) -> Option<&Prefix> {
         self.prefix.as_ref()
     }
 
@@ -1408,7 +1408,7 @@ impl ElementMethods for Element {
 
     // https://dom.spec.whatwg.org/#dom-element-prefix
     fn GetPrefix(&self) -> Option<DOMString> {
-        self.prefix.clone()
+        self.prefix.as_ref().map(|p| DOMString::from(&**p))
     }
 
     // https://dom.spec.whatwg.org/#dom-element-tagname

components/script/dom/htmlanchorelement.rs

@@ -25,7 +25,7 @@ use dom::node::{Node, document_from_node};
 use dom::urlhelper::UrlHelper;
 use dom::virtualmethods::VirtualMethods;
 use dom_struct::dom_struct;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 use net_traits::ReferrerPolicy;
 use num_traits::ToPrimitive;
 use script_traits::MozBrowserEvent;
@@ -43,7 +43,7 @@ pub struct HTMLAnchorElement {
 
 impl HTMLAnchorElement {
     fn new_inherited(local_name: LocalName,
-                     prefix: Option<DOMString>,
+                     prefix: Option<Prefix>,
                      document: &Document) -> HTMLAnchorElement {
         HTMLAnchorElement {
             htmlelement:
@@ -55,7 +55,7 @@ impl HTMLAnchorElement {
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLAnchorElement> {
         Node::reflect_node(box HTMLAnchorElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmlappletelement.rs

@@ -12,7 +12,7 @@ use dom::htmlelement::HTMLElement;
 use dom::node::Node;
 use dom::virtualmethods::VirtualMethods;
 use dom_struct::dom_struct;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 use style::attr::AttrValue;
 
 #[dom_struct]
@@ -22,7 +22,7 @@ pub struct HTMLAppletElement {
 
 impl HTMLAppletElement {
     fn new_inherited(local_name: LocalName,
-                     prefix: Option<DOMString>,
+                     prefix: Option<Prefix>,
                      document: &Document) -> HTMLAppletElement {
         HTMLAppletElement {
             htmlelement:
@@ -32,7 +32,7 @@ impl HTMLAppletElement {
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLAppletElement> {
         Node::reflect_node(box HTMLAppletElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmlareaelement.rs

@@ -20,7 +20,7 @@ use dom::node::{Node, document_from_node};
 use dom::virtualmethods::VirtualMethods;
 use dom_struct::dom_struct;
 use euclid::point::Point2D;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 use net_traits::ReferrerPolicy;
 use std::default::Default;
 use std::f32;
@@ -221,7 +221,7 @@ pub struct HTMLAreaElement {
 }
 
 impl HTMLAreaElement {
-    fn new_inherited(local_name: LocalName, prefix: Option<DOMString>, document: &Document) -> HTMLAreaElement {
+    fn new_inherited(local_name: LocalName, prefix: Option<Prefix>, document: &Document) -> HTMLAreaElement {
         HTMLAreaElement {
             htmlelement: HTMLElement::new_inherited(local_name, prefix, document),
             rel_list: Default::default(),
@@ -230,7 +230,7 @@ impl HTMLAreaElement {
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLAreaElement> {
         Node::reflect_node(box HTMLAreaElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmlaudioelement.rs

@@ -4,12 +4,11 @@
 
 use dom::bindings::codegen::Bindings::HTMLAudioElementBinding;
 use dom::bindings::js::Root;
-use dom::bindings::str::DOMString;
 use dom::document::Document;
 use dom::htmlmediaelement::HTMLMediaElement;
 use dom::node::Node;
 use dom_struct::dom_struct;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 
 #[dom_struct]
 pub struct HTMLAudioElement {
@@ -18,7 +17,7 @@ pub struct HTMLAudioElement {
 
 impl HTMLAudioElement {
     fn new_inherited(local_name: LocalName,
-                     prefix: Option<DOMString>,
+                     prefix: Option<Prefix>,
                      document: &Document) -> HTMLAudioElement {
         HTMLAudioElement {
             htmlmediaelement:
@@ -28,7 +27,7 @@ impl HTMLAudioElement {
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLAudioElement> {
         Node::reflect_node(box HTMLAudioElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmlbaseelement.rs

@@ -14,7 +14,7 @@ use dom::htmlelement::HTMLElement;
 use dom::node::{Node, UnbindContext, document_from_node};
 use dom::virtualmethods::VirtualMethods;
 use dom_struct::dom_struct;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 use servo_url::ServoUrl;
 use style::attr::AttrValue;
 
@@ -24,15 +24,15 @@ pub struct HTMLBaseElement {
 }
 
 impl HTMLBaseElement {
-    fn new_inherited(local_name: LocalName, prefix: Option<DOMString>, document: &Document) -> HTMLBaseElement {
+    fn new_inherited(local_name: LocalName, prefix: Option<Prefix>, document: &Document) -> HTMLBaseElement {
         HTMLBaseElement {
             htmlelement: HTMLElement::new_inherited(local_name, prefix, document)
         }
     }
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLBaseElement> {
         Node::reflect_node(box HTMLBaseElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmlbodyelement.rs

@@ -18,7 +18,7 @@ use dom::htmlelement::HTMLElement;
 use dom::node::{Node, document_from_node, window_from_node};
 use dom::virtualmethods::VirtualMethods;
 use dom_struct::dom_struct;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 use script_traits::ScriptMsg as ConstellationMsg;
 use servo_url::ServoUrl;
 use style::attr::AttrValue;
@@ -34,15 +34,15 @@ pub struct HTMLBodyElement {
 }
 
 impl HTMLBodyElement {
-    fn new_inherited(local_name: LocalName, prefix: Option<DOMString>, document: &Document)
+    fn new_inherited(local_name: LocalName, prefix: Option<Prefix>, document: &Document)
                      -> HTMLBodyElement {
         HTMLBodyElement {
             htmlelement: HTMLElement::new_inherited(local_name, prefix, document),
         }
     }
 
     #[allow(unrooted_must_root)]
-    pub fn new(local_name: LocalName, prefix: Option<DOMString>, document: &Document)
+    pub fn new(local_name: LocalName, prefix: Option<Prefix>, document: &Document)
                -> Root<HTMLBodyElement> {
         Node::reflect_node(box HTMLBodyElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmlbrelement.rs

@@ -4,28 +4,27 @@
 
 use dom::bindings::codegen::Bindings::HTMLBRElementBinding;
 use dom::bindings::js::Root;
-use dom::bindings::str::DOMString;
 use dom::document::Document;
 use dom::htmlelement::HTMLElement;
 use dom::node::Node;
 use dom_struct::dom_struct;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 
 #[dom_struct]
 pub struct HTMLBRElement {
     htmlelement: HTMLElement,
 }
 
 impl HTMLBRElement {
-    fn new_inherited(local_name: LocalName, prefix: Option<DOMString>, document: &Document) -> HTMLBRElement {
+    fn new_inherited(local_name: LocalName, prefix: Option<Prefix>, document: &Document) -> HTMLBRElement {
         HTMLBRElement {
             htmlelement: HTMLElement::new_inherited(local_name, prefix, document)
         }
     }
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLBRElement> {
         Node::reflect_node(box HTMLBRElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmlbuttonelement.rs

@@ -24,7 +24,7 @@ use dom::validation::Validatable;
 use dom::validitystate::{ValidityState, ValidationFlags};
 use dom::virtualmethods::VirtualMethods;
 use dom_struct::dom_struct;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 use std::cell::Cell;
 use std::default::Default;
 use style::element_state::*;
@@ -47,7 +47,7 @@ pub struct HTMLButtonElement {
 
 impl HTMLButtonElement {
     fn new_inherited(local_name: LocalName,
-                     prefix: Option<DOMString>,
+                     prefix: Option<Prefix>,
                      document: &Document) -> HTMLButtonElement {
         HTMLButtonElement {
             htmlelement:
@@ -60,7 +60,7 @@ impl HTMLButtonElement {
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLButtonElement> {
         Node::reflect_node(box HTMLButtonElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmlcanvaselement.rs

@@ -27,7 +27,7 @@ use dom::virtualmethods::VirtualMethods;
 use dom::webglrenderingcontext::{LayoutCanvasWebGLRenderingContextHelpers, WebGLRenderingContext};
 use dom_struct::dom_struct;
 use euclid::size::Size2D;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 use image::ColorType;
 use image::png::PNGEncoder;
 use ipc_channel::ipc::{self, IpcSender};
@@ -56,7 +56,7 @@ pub struct HTMLCanvasElement {
 
 impl HTMLCanvasElement {
     fn new_inherited(local_name: LocalName,
-                     prefix: Option<DOMString>,
+                     prefix: Option<Prefix>,
                      document: &Document) -> HTMLCanvasElement {
         HTMLCanvasElement {
             htmlelement: HTMLElement::new_inherited(local_name, prefix, document),
@@ -66,7 +66,7 @@ impl HTMLCanvasElement {
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLCanvasElement> {
         Node::reflect_node(box HTMLCanvasElement::new_inherited(local_name, prefix, document),
                            document,

components/script/dom/htmldataelement.rs

@@ -10,7 +10,7 @@ use dom::document::Document;
 use dom::htmlelement::HTMLElement;
 use dom::node::Node;
 use dom_struct::dom_struct;
-use html5ever::LocalName;
+use html5ever::{LocalName, Prefix};
 
 #[dom_struct]
 pub struct HTMLDataElement {
@@ -19,7 +19,7 @@ pub struct HTMLDataElement {
 
 impl HTMLDataElement {
     fn new_inherited(local_name: LocalName,
-                     prefix: Option<DOMString>,
+                     prefix: Option<Prefix>,
                      document: &Document) -> HTMLDataElement {
         HTMLDataElement {
             htmlelement: HTMLElement::new_inherited(local_name, prefix, document)
@@ -28,7 +28,7 @@ impl HTMLDataElement {
 
     #[allow(unrooted_must_root)]
     pub fn new(local_name: LocalName,
-               prefix: Option<DOMString>,
+               prefix: Option<Prefix>,
                document: &Document) -> Root<HTMLDataElement> {
         Node::reflect_node(box HTMLDataElement::new_inherited(local_name, prefix, document),
                            document,