visit exclamation token

Author: Kingwl

src/compiler/visitor.ts

@@ -268,7 +268,7 @@ namespace ts {
                     nodesVisitor((<PropertyDeclaration>node).decorators, visitor, isDecorator),
                     nodesVisitor((<PropertyDeclaration>node).modifiers, visitor, isModifier),
                     visitNode((<PropertyDeclaration>node).name, visitor, isPropertyName),
-                    visitNode((<PropertyDeclaration>node).questionToken, tokenVisitor, isToken),
+                    visitNode((<PropertyDeclaration>node).questionToken, tokenVisitor, isToken) || visitNode((<PropertyDeclaration>node).exclamationToken, tokenVisitor, isToken),
                     visitNode((<PropertyDeclaration>node).type, visitor, isTypeNode),
                     visitNode((<PropertyDeclaration>node).initializer, visitor, isExpression));