Auto merge of #23748 - saschanaz:default-dict, r=Manishearth

Sync WebIDL.py with gecko

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The new change requires default dictionary value for optional dictionary-type arguments.

---
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- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #23703

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- [x] There are tests for these changes

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1 files changed, 4 insertions, 4 deletions

diff --git a/components/script/dom/bindings/codegen/parser/tests/test_attr.py b/components/script/dom/bindings/codegen/parser/tests/test_attr.py
index ad7aabc1918..35f680aaa82 100644
--- a/components/script/dom/bindings/codegen/parser/tests/test_attr.py
+++ b/components/script/dom/bindings/codegen/parser/tests/test_attr.py
@@ -133,7 +133,7 @@ def WebIDLTest(parser, harness):
           };
         """)
         results = parser.finish()
-    except Exception, x:
+    except Exception as x:
         threw = True
     harness.ok(threw, "Should not allow [SetterThrows] on readonly attributes")
 
@@ -146,7 +146,7 @@ def WebIDLTest(parser, harness):
           };
         """)
         results = parser.finish()
-    except Exception, x:
+    except Exception as x:
         threw = True
     harness.ok(threw, "Should spell [Throws] correctly")
 
@@ -159,7 +159,7 @@ def WebIDLTest(parser, harness):
           };
         """)
         results = parser.finish()
-    except Exception, x:
+    except Exception as x:
         threw = True
     harness.ok(threw, "Should not allow [SameObject] on attributes not of interface type")
 
@@ -172,6 +172,6 @@ def WebIDLTest(parser, harness):
           };
         """)
         results = parser.finish()
-    except Exception, x:
+    except Exception as x:
         threw = True
     harness.ok(not threw, "Should allow [SameObject] on attributes of interface type")