Convert vectors to list aliases

This CL converts a few more std::vector<std::unique_ptr<foo>>'s to
FooList aliases.

Change-Id: If0dd672f11beaeabd9e89e82903c2174b11be6e1
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/19103
Reviewed-by: David Neto <dneto@google.com>
diff --git a/src/reader/spirv/function.cc b/src/reader/spirv/function.cc
index 94520c4..97626f8 100644
--- a/src/reader/spirv/function.cc
+++ b/src/reader/spirv/function.cc
@@ -92,7 +92,7 @@
            << function_.result_id();
   }
 
-  std::vector<std::unique_ptr<ast::Variable>> ast_params;
+  ast::VariableList ast_params;
   function_.ForEachParam(
       [this, &ast_params](const spvtools::opt::Instruction* param) {
         auto* ast_type = parser_impl_.ConvertType(param->type_id());
diff --git a/src/reader/spirv/function.h b/src/reader/spirv/function.h
index 9e6a809..2b7e58d 100644
--- a/src/reader/spirv/function.h
+++ b/src/reader/spirv/function.h
@@ -53,9 +53,7 @@
   bool failed() const { return !success(); }
 
   /// @returns the body of the function.
-  const std::vector<std::unique_ptr<ast::Statement>>& ast_body() {
-    return ast_body_;
-  }
+  const ast::StatementList& ast_body() { return ast_body_; }
 
   /// Records failure.
   /// @returns a FailStream on which to emit diagnostics.
@@ -91,7 +89,7 @@
   FailStream& fail_stream_;
   Namer& namer_;
   const spvtools::opt::Function& function_;
-  std::vector<std::unique_ptr<ast::Statement>> ast_body_;
+  ast::StatementList ast_body_;
 };
 
 }  // namespace spirv
diff --git a/src/reader/spirv/parser_impl_test_helper.h b/src/reader/spirv/parser_impl_test_helper.h
index 7c5f15f..e6cb026 100644
--- a/src/reader/spirv/parser_impl_test_helper.h
+++ b/src/reader/spirv/parser_impl_test_helper.h
@@ -66,8 +66,7 @@
 /// Returns the string dump of a function body.
 /// @param body the statement in the body
 /// @returnss the string dump of a function body.
-inline std::string ToString(
-    const std::vector<std::unique_ptr<ast::Statement>>& body) {
+inline std::string ToString(const ast::StatementList& body) {
   std::ostringstream outs;
   for (const auto& stmt : body) {
     stmt->to_str(outs, 0);