Fix outdated analyzer API usage (#1150)

Author: kevmoo

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 * Require `package:analyzer` `^5.1.0`.
 * Format unnamed libraries.
+* Require Dart 2.18.
 
 # 2.2.4
 

lib/src/source_visitor.dart

@@ -574,9 +574,9 @@ class SourceVisitor extends ThrowingAstVisitor {
       token(node.catchKeyword);
       space();
       token(node.leftParenthesis);
-      visit(node.exceptionParameter2);
+      visit(node.exceptionParameter);
       token(node.comma, after: space);
-      visit(node.stackTraceParameter2);
+      visit(node.stackTraceParameter);
       token(node.rightParenthesis);
       space();
     } else {

pubspec.yaml

@@ -6,10 +6,10 @@ description: >-
   Provides an API and a CLI tool.
 repository: https://github.com/dart-lang/dart_style
 environment:
-  sdk: ">=2.17.0 <3.0.0"
+  sdk: ">=2.18.0 <3.0.0"
 
 dependencies:
-  analyzer: '^5.1.0'
+  analyzer: ^5.2.0
   args: ">=1.0.0 <3.0.0"
   path: ^1.0.0
   pub_semver: ">=1.4.4 <3.0.0"