Auto merge of #23711 - saschanaz:frompoint, r=Manishearth

Implement DOMPoint.fromPoint

<!-- Please describe your changes on the following line: -->

Implements DOMPoint.fromPoint and fixes codegen to use default value when an optional dictionary member got `undefined`.

PS: The codegen change is about:

```webidl
dictionary MyDictionary {
  optional short myMember = 0;
  short anotherMember;
}

[Exposed=Window, Constructor]
interface MyInterface {
  void myMethod(optional MyDictionary myDict);
};
```

```js
// The following two must behave same
new MyInterface().myMethod({ myMember: undefined, anotherMember = 0 });
new MyInterface().myMethod({ anotherMember = 0 });
```

---
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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 #23710

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- [x] There are tests for these changes

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components/script/dom/bindings/codegen/CodegenRust.py

@@ -6414,7 +6414,8 @@ class CGDictionary(CGThing):
         conversion = (
             "{\n"
             "    rooted!(in(cx) let mut rval = UndefinedValue());\n"
-            "    if r#try!(get_dictionary_property(cx, object.handle(), \"%s\", rval.handle_mut())) {\n"
+            "    if r#try!(get_dictionary_property(cx, object.handle(), \"%s\", rval.handle_mut()))"
+            " && !rval.is_undefined() {\n"
             "%s\n"
             "    } else {\n"
             "%s\n"

components/script/dom/dompoint.rs

@@ -40,6 +40,11 @@ impl DOMPoint {
         Ok(DOMPoint::new(global, x, y, z, w))
     }
 
+    // https://drafts.fxtf.org/geometry/#dom-dompoint-frompoint
+    pub fn FromPoint(global: &GlobalScope, init: &DOMPointInit) -> DomRoot<Self> {
+        Self::new_from_init(global, init)
+    }
+
     pub fn new_from_init(global: &GlobalScope, p: &DOMPointInit) -> DomRoot<DOMPoint> {
         DOMPoint::new(global, p.x, p.y, p.z, p.w)
     }

components/script/dom/dompointreadonly.rs

@@ -2,6 +2,7 @@
  * 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 crate::dom::bindings::codegen::Bindings::DOMPointBinding::DOMPointInit;
 use crate::dom::bindings::codegen::Bindings::DOMPointReadOnlyBinding::{
     DOMPointReadOnlyMethods, Wrap,
 };
@@ -50,6 +51,11 @@ impl DOMPointReadOnly {
     ) -> Fallible<DomRoot<DOMPointReadOnly>> {
         Ok(DOMPointReadOnly::new(global, x, y, z, w))
     }
+
+    // https://drafts.fxtf.org/geometry/#dom-dompointreadonly-frompoint
+    pub fn FromPoint(global: &GlobalScope, init: &DOMPointInit) -> DomRoot<Self> {
+        Self::new(global, init.x, init.y, init.z, init.w)
+    }
 }
 
 impl DOMPointReadOnlyMethods for DOMPointReadOnly {

components/script/dom/webidls/DOMPoint.webidl

@@ -14,6 +14,8 @@
              optional unrestricted double z = 0, optional unrestricted double w = 1),
  Exposed=(Window,Worker)]
 interface DOMPoint : DOMPointReadOnly {
+    [NewObject] static DOMPoint fromPoint(optional DOMPointInit other = null);
+
     inherit attribute unrestricted double x;
     inherit attribute unrestricted double y;
     inherit attribute unrestricted double z;

components/script/dom/webidls/DOMPointReadOnly.webidl

@@ -14,6 +14,8 @@
              optional unrestricted double z = 0, optional unrestricted double w = 1),
  Exposed=(Window,Worker)]
 interface DOMPointReadOnly {
+    [NewObject] static DOMPointReadOnly fromPoint(optional DOMPointInit other = null);
+
     readonly attribute unrestricted double x;
     readonly attribute unrestricted double y;
     readonly attribute unrestricted double z;