Auto merge of #11155 - emilio:codegen-dict-keyword, r=Ms2ger

codegen: Fix dictionary handling and semantics

Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data:
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #11152 (github issue number if applicable).

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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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Fixes #11152

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components/script/dom/webidls/TestBinding.webidl

@@ -30,6 +30,13 @@ dictionary TestDictionary {
   object objectValue;
   TestDictionaryDefaults dict;
   sequence<TestDictionaryDefaults> seqDict;
+  // Reserved rust keyword
+  DOMString type;
+  // These are used to test bidirectional conversion
+  // and differentiation of non-required and nullable types
+  // in dictionaries.
+  DOMString? nonRequiredNullable;
+  DOMString? nonRequiredNullable2;
 };
 
 dictionary TestDictionaryDefaults {
@@ -196,6 +203,8 @@ interface TestBinding {
   (sequence<long> or boolean)? receiveNullableUnion4();
   (unsigned long or boolean)? receiveNullableUnion5();
   sequence<long>? receiveNullableSequence();
+  TestDictionary receiveTestDictionaryWithSuccessOnKeyword();
+  boolean dictMatchesPassedValues(TestDictionary arg);
 
   void passBoolean(boolean arg);
   void passByte(byte arg);