Update for SyntaxTransformVisitor SPI

Author: hamishknight

lib/ASTGen/Sources/ASTGen/ASTGen.swift

@@ -1,5 +1,8 @@
 import CASTBridging
 import SwiftParser
+
+// Needed to use SyntaxTransformVisitor's visit method.
+@_spi(SyntaxTransformVisitor)
 import SwiftSyntax
 
 extension Array {

lib/ASTGen/Sources/ASTGen/Decls.swift

@@ -1,5 +1,8 @@
 import CASTBridging
 import SwiftParser
+
+// Needed to use SyntaxTransformVisitor's visit method.
+@_spi(SyntaxTransformVisitor)
 import SwiftSyntax
 
 extension ASTGenVisitor {

lib/ASTGen/Sources/ASTGen/Exprs.swift

@@ -1,5 +1,8 @@
 import CASTBridging
 import SwiftParser
+
+// Needed to use SyntaxTransformVisitor's visit method.
+@_spi(SyntaxTransformVisitor)
 import SwiftSyntax
 
 extension ASTGenVisitor {

lib/ASTGen/Sources/ASTGen/Generics.swift

@@ -1,5 +1,8 @@
 import CASTBridging
 import SwiftParser
+
+// Needed to use SyntaxTransformVisitor's visit method.
+@_spi(SyntaxTransformVisitor)
 import SwiftSyntax
 
 extension ASTGenVisitor {

lib/ASTGen/Sources/ASTGen/Macros.swift

@@ -14,12 +14,15 @@ import CASTBridging
 import SwiftDiagnostics
 import SwiftOperators
 import SwiftParser
-import SwiftSyntax
 import SwiftSyntaxBuilder
 import SwiftSyntaxMacros
 import SwiftSyntaxMacroExpansion
 import SwiftCompilerPluginMessageHandling
 
+// Needed to use SyntaxTransformVisitor's visit method.
+@_spi(SyntaxTransformVisitor)
+import SwiftSyntax
+
 extension SyntaxProtocol {
   func token(at position: AbsolutePosition) -> TokenSyntax? {
     // If the position isn't within this node at all, return early.

lib/ASTGen/Sources/ASTGen/Misc.swift

@@ -1,5 +1,8 @@
 import CASTBridging
 import SwiftParser
+
+// Needed to use SyntaxTransformVisitor's visit method.
+@_spi(SyntaxTransformVisitor)
 import SwiftSyntax
 
 extension ASTGenVisitor {

lib/ASTGen/Sources/ASTGen/Stmts.swift

@@ -1,5 +1,8 @@
 import CASTBridging
 import SwiftParser
+
+// Needed to use SyntaxTransformVisitor's visit method.
+@_spi(SyntaxTransformVisitor)
 import SwiftSyntax
 
 extension ASTGenVisitor {

lib/ASTGen/Sources/ASTGen/Types.swift

@@ -1,5 +1,8 @@
 import CASTBridging
 import SwiftParser
+
+// Needed to use SyntaxTransformVisitor's visit method.
+@_spi(SyntaxTransformVisitor)
 import SwiftSyntax
 
 extension ASTGenVisitor {