Auto merge of #18539 - emilio:dom-conversion-fixes, r=nox

script: a couple DOM conversion fixes

Fixes https://github.com/servo/servo/issues/18535

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

@@ -4938,8 +4938,6 @@ class CGDOMJSProxyHandler_defineProperty(CGAbstractExternMethod):
             set += ("if RUST_JSID_IS_STRING(id) {\n" +
                     CGIndenter(CGProxyNamedSetter(self.descriptor)).define() +
                     "    return (*opresult).succeed();\n" +
-                    "} else {\n" +
-                    "    return false;\n" +
                     "}\n")
         else:
             set += ("if RUST_JSID_IS_STRING(id) {\n" +
@@ -4948,7 +4946,7 @@ class CGDOMJSProxyHandler_defineProperty(CGAbstractExternMethod):
                     "        return (*opresult).failNoNamedSetter();\n"
                     "    }\n"
                     "}\n")
-            set += "return proxyhandler::define_property(%s);" % ", ".join(a.name for a in self.args)
+        set += "return proxyhandler::define_property(%s);" % ", ".join(a.name for a in self.args)
         return set
 
     def definition_body(self):

components/script/dom/bindings/conversions.rs

@@ -84,13 +84,13 @@ impl<T: Float + FromJSValConvertible<Config=()>> FromJSValConvertible for Finite
                          value: HandleValue,
                          option: ())
                          -> Result<ConversionResult<Finite<T>>, ()> {
-        let result = match FromJSValConvertible::from_jsval(cx, value, option) {
-            Ok(ConversionResult::Success(v)) => v,
-            Ok(ConversionResult::Failure(error)) => {
+        let result = match FromJSValConvertible::from_jsval(cx, value, option)? {
+            ConversionResult::Success(v) => v,
+            ConversionResult::Failure(error) => {
+                // FIXME(emilio): Why throwing instead of propagating the error?
                 throw_type_error(cx, &error);
                 return Err(());
             }
-            _ => return Err(()),
         };
         match Finite::new(result) {
             Some(v) => Ok(ConversionResult::Success(v)),

components/script/dom/bindings/utils.rs

@@ -414,18 +414,22 @@ unsafe fn generic_call(cx: *mut JSContext,
                                               -> bool)
                        -> bool {
     let args = CallArgs::from_vp(vp, argc);
+
+    let info = RUST_FUNCTION_VALUE_TO_JITINFO(JS_CALLEE(cx, vp));
+    let proto_id = (*info).protoID;
+
     let thisobj = args.thisv();
     if !thisobj.get().is_null_or_undefined() && !thisobj.get().is_object() {
+        throw_invalid_this(cx, proto_id);
         return false;
     }
+
     let obj = if thisobj.get().is_object() {
         thisobj.get().to_object()
     } else {
         GetGlobalForObjectCrossCompartment(JS_CALLEE(cx, vp).to_object_or_null())
     };
     rooted!(in(cx) let obj = obj);
-    let info = RUST_FUNCTION_VALUE_TO_JITINFO(JS_CALLEE(cx, vp));
-    let proto_id = (*info).protoID;
     let depth = (*info).depth;
     let proto_check = |class: &'static DOMClass| {
         class.interface_chain[depth as usize] as u16 == proto_id