Include CompilationUnit begin/endToken(s) with Fasta.

pkg/analyzer/test/generated/parser_test.dart

Index: pkg/analyzer/test/generated/parser_test.dart
diff --git a/pkg/analyzer/test/generated/parser_test.dart b/pkg/analyzer/test/generated/parser_test.dart
index b00f82ea60625a619e54cc4211ed120aa2fb5441..348274eece669167e00ada5a41f0bbf1d81bb5cf 100644
--- a/pkg/analyzer/test/generated/parser_test.dart
+++ b/pkg/analyzer/test/generated/parser_test.dart
@@ -13400,6 +13400,9 @@ abstract class TopLevelParserTestMixin implements AbstractParserTestCase {
     expect(unit.scriptTag, isNull);
     expect(unit.directives, hasLength(0));
     expect(unit.declarations, hasLength(0));
+    expect(unit.beginToken, isNotNull);
+    expect(unit.endToken, isNotNull);
+    expect(unit.endToken.type, TokenType.EOF);
   }
 
   void test_parseCompilationUnit_exportAsPrefix() {
@@ -13460,6 +13463,10 @@ abstract class TopLevelParserTestMixin implements AbstractParserTestCase {
     expect(unit.scriptTag, isNull);
     expect(unit.directives, hasLength(0));
     expect(unit.declarations, hasLength(1));
+    expect(unit.beginToken, isNotNull);
+    expect(unit.beginToken.keyword, Keyword.CLASS);
+    expect(unit.endToken, isNotNull);
+    expect(unit.endToken.type, TokenType.EOF);
   }
 
   void test_parseCompilationUnit_typedefAsPrefix() {