Auto merge of #23653 - Manishearth:nested, r=jdm

Improve support for nested dictionaries

Fixes https://github.com/servo/servo/issues/23640

Some IDLs need `= null`, that's something that needs to be updated upstream too.

After talking with @bzbarsky I realized that it was our IDLs which were incorrect, causing Options to appear where we don't want them to. In the media code we _do_ want Options. `= null` is the correct fix for that (and should be upstreamed).

r? @jdm

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components/script/dom/bindings/codegen/parser/WebIDL.py

@@ -4611,7 +4611,8 @@ class IDLArgument(IDLObjectWithIdentifier):
 
         if ((self.type.isDictionary() or
              self.type.isUnion() and self.type.unroll().hasDictionaryType()) and
-            self.optional and not self.defaultValue and not self.variadic):
+            self.optional and not self.defaultValue and not self.variadic and
+            not self.dictionaryMember):
             # Default optional non-variadic dictionary arguments to null,
             # for simplicity, so the codegen doesn't have to special-case this.
             self.defaultValue = IDLNullValue(self.location)

components/script/dom/bindings/codegen/parser/undo-dictionary-optional.patch

@@ -1,12 +0,0 @@
---- WebIDL.py
-+++ WebIDL.py
-@@ -4570,8 +4570,7 @@ class IDLArgument(IDLObjectWithIdentifier):
- 
-         if ((self.type.isDictionary() or
-              self.type.isUnion() and self.type.unroll().hasDictionaryType()) and
--            self.optional and not self.defaultValue and not self.variadic and
--            not self.dictionaryMember):
-+            self.optional and not self.defaultValue and not self.variadic):
-             # Default optional non-variadic dictionary arguments to null,
-             # for simplicity, so the codegen doesn't have to special-case this.
-             self.defaultValue = IDLNullValue(self.location)

components/script/dom/bindings/codegen/parser/update.sh

@@ -5,7 +5,6 @@ patch < pref-main-thread.patch
 patch < callback-location.patch
 patch < union-typedef.patch
 patch < inline.patch
-patch < undo-dictionary-optional.patch
 
 wget https://hg.mozilla.org/mozilla-central/archive/tip.tar.gz/dom/bindings/parser/tests/ -O tests.tar.gz
 rm -r tests

components/script/dom/mediadevices.rs

@@ -78,11 +78,11 @@ fn convert_constraints(js: &BooleanOrMediaTrackConstraints) -> Option<MediaTrack
         BooleanOrMediaTrackConstraints::Boolean(true) => Some(Default::default()),
         BooleanOrMediaTrackConstraints::MediaTrackConstraints(ref c) => {
             Some(MediaTrackConstraintSet {
-                height: convert_culong(&c.parent.height),
+                height: c.parent.height.as_ref().and_then(convert_culong),
-                width: convert_culong(&c.parent.width),
+                width: c.parent.width.as_ref().and_then(convert_culong),
-                aspect: convert_cdouble(&c.parent.aspectRatio),
+                aspect: c.parent.aspectRatio.as_ref().and_then(convert_cdouble),
-                frame_rate: convert_cdouble(&c.parent.frameRate),
+                frame_rate: c.parent.frameRate.as_ref().and_then(convert_cdouble),
-                sample_rate: convert_culong(&c.parent.sampleRate),
+                sample_rate: c.parent.sampleRate.as_ref().and_then(convert_culong),
             })
         },
     }

components/script/dom/webidls/DOMQuad.webidl

@@ -25,8 +25,8 @@ interface DOMQuad {
 };
 
 dictionary DOMQuadInit {
-    DOMPointInit p1;
+    DOMPointInit p1 = null;
-    DOMPointInit p2;
+    DOMPointInit p2 = null;
-    DOMPointInit p3;
+    DOMPointInit p3 = null;
-    DOMPointInit p4;
+    DOMPointInit p4 = null;
 };

components/script/dom/webidls/TestBinding.webidl

@@ -32,7 +32,7 @@ dictionary TestDictionary {
   Blob interfaceValue;
   any anyValue;
   object objectValue;
-  TestDictionaryDefaults dict;
+  TestDictionaryDefaults dict = null;
   sequence<TestDictionaryDefaults> seqDict;
   // Testing codegen to import Element correctly, ensure no other code references Element directly
   sequence<Element> elementSequence;