Auto merge of #8412 - ecoal95:webidl-sequence-return, r=jdm

Add WebIDL sequence return values

And use it for `WebGLRenderingContext::getSupportedExtensions`.
Part of #544

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1 files changed, 6 insertions, 1 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 5ac6c455e39..260ef1e9006 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -1295,7 +1295,12 @@ def getRetvalDeclarationForType(returnType, descriptorProvider):
     if returnType.isObject() or returnType.isSpiderMonkeyInterface():
         return CGGeneric("*mut JSObject")
     if returnType.isSequence():
-        raise TypeError("We don't support sequence return values")
+        inner = returnType.unroll()
+        result = getRetvalDeclarationForType(inner, descriptorProvider)
+        result = CGWrapper(result, pre="Vec<", post=">")
+        if returnType.nullable():
+            result = CGWrapper(result, pre="Option<", post=">")
+        return result
     if returnType.isDictionary():
         nullable = returnType.nullable()
         dictName = returnType.inner.name if nullable else returnType.name