remove languageVersionField and update scanner tests

Change-Id: I5fbb25d5f743fc00fe188da02390a67ded8b1c69
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/100980
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Dan Rubel <danrubel@google.com>
diff --git a/pkg/front_end/lib/src/fasta/scanner.dart b/pkg/front_end/lib/src/fasta/scanner.dart
index f9f1741..7df276f 100644
--- a/pkg/front_end/lib/src/fasta/scanner.dart
+++ b/pkg/front_end/lib/src/fasta/scanner.dart
@@ -13,8 +13,6 @@
 
 import 'scanner/string_scanner.dart' show StringScanner;
 
-import 'scanner/token.dart' show LanguageVersionToken;
-
 import 'scanner/utf8_bytes_scanner.dart' show Utf8BytesScanner;
 
 import 'scanner/recover.dart' show defaultRecoveryStrategy;
@@ -53,10 +51,6 @@
   /// Returns true if an error occured during [tokenize].
   bool get hasErrors;
 
-  /// The token containing the language version (e.g. `// @dart = 2.1`)
-  /// or `null` if none.
-  LanguageVersionToken get languageVersion;
-
   List<int> get lineStarts;
 
   /// Configure which tokens are produced.
@@ -67,12 +61,10 @@
 
 class ScannerResult {
   final Token tokens;
-  final LanguageVersionToken languageVersion;
   final List<int> lineStarts;
   final bool hasErrors;
 
-  ScannerResult(
-      this.tokens, this.languageVersion, this.lineStarts, this.hasErrors);
+  ScannerResult(this.tokens, this.lineStarts, this.hasErrors);
 }
 
 /// Scan/tokenize the given UTF8 [bytes].
@@ -116,6 +108,5 @@
     recover ??= defaultRecoveryStrategy;
     tokens = recover(bytes, tokens, scanner.lineStarts);
   }
-  return new ScannerResult(
-      tokens, scanner.languageVersion, scanner.lineStarts, scanner.hasErrors);
+  return new ScannerResult(tokens, scanner.lineStarts, scanner.hasErrors);
 }
diff --git a/pkg/front_end/lib/src/fasta/scanner/abstract_scanner.dart b/pkg/front_end/lib/src/fasta/scanner/abstract_scanner.dart
index 79ba63d..3c18577 100644
--- a/pkg/front_end/lib/src/fasta/scanner/abstract_scanner.dart
+++ b/pkg/front_end/lib/src/fasta/scanner/abstract_scanner.dart
@@ -65,9 +65,6 @@
   /// such as 'required' and 'late'.
   bool _enableNonNullable = false;
 
-  @override
-  LanguageVersionToken languageVersion;
-
   /**
    * The string offset for the next token that will be created.
    *
@@ -976,7 +973,7 @@
       return tokenizeSingleLineCommentRest(next, start, false);
     }
 
-    languageVersion = createLanguageVersionToken(start, major, minor);
+    var languageVersion = createLanguageVersionToken(start, major, minor);
     if (languageVersionChanged != null) {
       // TODO(danrubel): make this required and remove the languageVersion field
       languageVersionChanged(this, languageVersion);
diff --git a/pkg/front_end/test/scanner_fasta_test.dart b/pkg/front_end/test/scanner_fasta_test.dart
index 914ae8c..9af6744 100644
--- a/pkg/front_end/test/scanner_fasta_test.dart
+++ b/pkg/front_end/test/scanner_fasta_test.dart
@@ -761,7 +761,7 @@
 // @dart = 2.3
 main() {}
 ''');
-    expect(result.languageVersion, isNull);
+    expect(languageVersion, isNull);
     expectComments(result.tokens, [], -1);
   }
 
@@ -773,8 +773,8 @@
 import 'foo.dart';
 main() {}
 ''');
-    expect(result.languageVersion.major, 2);
-    expect(result.languageVersion.minor, 3);
+    expect(languageVersion.major, 2);
+    expect(languageVersion.minor, 3);
     expectComments(
         result.tokens,
         [
@@ -790,8 +790,8 @@
 // @dart = 2.3
 main() {}
 ''');
-    expect(result.languageVersion.major, 2);
-    expect(result.languageVersion.minor, 3);
+    expect(languageVersion.major, 2);
+    expect(languageVersion.minor, 3);
     expectComments(result.tokens, ['// @dart = 2.3'], 0);
   }
 
@@ -800,7 +800,7 @@
 // @dart = 2.3 x
 main() {}
 ''');
-    expect(result.languageVersion, isNull);
+    expect(languageVersion, isNull);
     expectComments(result.tokens, ['// @dart = 2.3 x'], -1);
   }
 
@@ -809,8 +809,8 @@
 // @dart = 2.3
 main() {}
 ''', includeComments: false);
-    expect(result.languageVersion.major, 2);
-    expect(result.languageVersion.minor, 3);
+    expect(languageVersion.major, 2);
+    expect(languageVersion.minor, 3);
     expectComments(result.tokens, [], -1);
   }
 
@@ -820,8 +820,8 @@
 import 'foo.dart';
 main() {}
 ''');
-    expect(result.languageVersion.major, 2);
-    expect(result.languageVersion.minor, 3);
+    expect(languageVersion.major, 2);
+    expect(languageVersion.minor, 3);
     expectComments(result.tokens, ['// @dart = 2.3'], 0);
   }
 
@@ -832,8 +832,8 @@
 import 'foo.dart';
 main() {}
 ''');
-    expect(result.languageVersion.major, 2);
-    expect(result.languageVersion.minor, 3);
+    expect(languageVersion.major, 2);
+    expect(languageVersion.minor, 3);
     expectComments(result.tokens.next, ['// @dart = 2.3'], 0);
   }
 
@@ -843,8 +843,8 @@
 library foo;
 main() {}
 ''');
-    expect(result.languageVersion.major, 2);
-    expect(result.languageVersion.minor, 3);
+    expect(languageVersion.major, 2);
+    expect(languageVersion.minor, 3);
     expectComments(result.tokens, ['// @dart = 2.3'], 0);
   }
 
@@ -854,8 +854,8 @@
 library foo;
 main() {}
 ''');
-    expect(result.languageVersion.major, 2);
-    expect(result.languageVersion.minor, 3);
+    expect(languageVersion.major, 2);
+    expect(languageVersion.minor, 3);
     expectComments(result.tokens, ['// @dart=2.3'], 0);
   }
 
@@ -865,7 +865,7 @@
 library foo;
 main() {}
 ''');
-    expect(result.languageVersion, isNull);
+    expect(languageVersion, isNull);
     expectComments(result.tokens, ['// @dart = 2.'], -1);
   }
 
@@ -875,7 +875,7 @@
 library foo;
 main() {}
 ''');
-    expect(result.languageVersion, isNull);
+    expect(languageVersion, isNull);
     expectComments(result.tokens, ['// @dart = blat'], -1);
   }
 
@@ -885,7 +885,7 @@
 library foo;
 main() {}
 ''');
-    expect(result.languageVersion, isNull);
+    expect(languageVersion, isNull);
     expectComments(result.tokens, ['// @dart = 2.x'], -1);
   }