Auto merge of #17945 - ferjm:typedef.dom.binding, r=jdm

Generate DOM bindings imports for webidl typedefs

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors

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

@@ -1848,7 +1848,8 @@ class CGImports(CGWrapper):
     """
     Generates the appropriate import/use statements.
     """
-    def __init__(self, child, descriptors, callbacks, dictionaries, enums, imports, config, ignored_warnings=None):
+    def __init__(self, child, descriptors, callbacks, dictionaries, enums, typedefs, imports, config,
+                 ignored_warnings=None):
         """
         Adds a set of imports.
         """
@@ -1937,6 +1938,11 @@ class CGImports(CGWrapper):
         for d in dictionaries:
             types += componentTypes(d)
 
+        # Import the type names used in the typedefs that are being defined.
+        for t in typedefs:
+            if not t.innerType.isCallback():
+                types += componentTypes(t.innerType)
+
         # Normalize the types we've collected and remove any ones which can't be imported.
         types = removeWrapperAndNullableTypes(types)
 
@@ -2292,6 +2298,7 @@ def UnionTypes(descriptors, dictionaries, callbacks, typedefs, config):
                      callbacks=[],
                      dictionaries=[],
                      enums=[],
+                     typedefs=[],
                      imports=imports,
                      config=config,
                      ignored_warnings=[])
@@ -5507,15 +5514,17 @@ class CGWeakReferenceableTrait(CGThing):
         return self.code
 
 
-def generate_imports(config, cgthings, descriptors, callbacks=None, dictionaries=None, enums=None):
+def generate_imports(config, cgthings, descriptors, callbacks=None, dictionaries=None, enums=None, typedefs=None):
     if not callbacks:
         callbacks = []
     if not dictionaries:
         dictionaries = []
     if not enums:
         enums = []
+    if not typedefs:
+        typedefs = []
 
-    return CGImports(cgthings, descriptors, callbacks, dictionaries, enums, [
+    return CGImports(cgthings, descriptors, callbacks, dictionaries, enums, typedefs, [
         'core::nonzero::NonZero',
         'js',
         'js::JSCLASS_GLOBAL_SLOT_COUNT',
@@ -6220,7 +6229,7 @@ class CGBindingRoot(CGThing):
         # Do codegen for all the enums.
         cgthings = [CGEnum(e) for e in enums]
 
-        # Do codegen for all the typdefs
+        # Do codegen for all the typedefs
         for t in typedefs:
             typeName = getRetvalDeclarationForType(t.innerType, config.getDescriptorProvider())
             substs = {
@@ -6258,7 +6267,7 @@ class CGBindingRoot(CGThing):
 
         # Add imports
         curr = generate_imports(config, curr, callbackDescriptors, mainCallbacks,
-                                dictionaries, enums)
+                                dictionaries, enums, typedefs)
 
         # Add the auto-generated comment.
         curr = CGWrapper(curr, pre=AUTOGENERATED_WARNING_COMMENT)
@@ -7060,7 +7069,7 @@ class GlobalGenRoots():
             CGRegisterProxyHandlers(config),
         ], "\n")
 
-        return CGImports(code, descriptors=[], callbacks=[], dictionaries=[], enums=[], imports=[
+        return CGImports(code, descriptors=[], callbacks=[], dictionaries=[], enums=[], typedefs=[], imports=[
             'dom::bindings::codegen::Bindings',
             'dom::bindings::codegen::PrototypeList::Proxies',
             'libc',