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, 2 insertions, 2 deletions

diff --git a/components/script/dom/bindings/codegen/parser/tests/test_interface_maplikesetlikeiterable.py b/components/script/dom/bindings/codegen/parser/tests/test_interface_maplikesetlikeiterable.py
index ee5d870c200..72aa7617b84 100644
--- a/components/script/dom/bindings/codegen/parser/tests/test_interface_maplikesetlikeiterable.py
+++ b/components/script/dom/bindings/codegen/parser/tests/test_interface_maplikesetlikeiterable.py
@@ -37,10 +37,10 @@ def WebIDLTest(parser, harness):
             p.finish()
             harness.ok(False,
                        prefix + " - Interface passed when should've failed")
-        except WebIDL.WebIDLError, e:
+        except WebIDL.WebIDLError as e:
             harness.ok(True,
                        prefix + " - Interface failed as expected")
-        except Exception, e:
+        except Exception as e:
             harness.ok(False,
                        prefix + " - Interface failed but not as a WebIDLError exception: %s" % e)