Remove package imports from itself.

pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart

Index: pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart b/pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart
index 5a14cae0ff85418224322eeffdf0f131ad1e142a..198b5839396567bb34467d2b8c681a613ab65b85 100644
--- a/pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart
+++ b/pkg/front_end/lib/src/fasta/analyzer/ast_builder.dart
@@ -9,10 +9,8 @@ import 'package:analyzer/dart/ast/ast_factory.dart' show AstFactory;
 import 'package:analyzer/dart/ast/standard_ast_factory.dart' as standard;
 import 'package:analyzer/dart/ast/token.dart' as analyzer show Token;
 import 'package:analyzer/dart/element/element.dart' show Element;
-import 'package:front_end/src/fasta/parser/parser.dart'
-    show FormalParameterType;
-import 'package:front_end/src/fasta/scanner/token.dart'
-    show BeginGroupToken, Token;
+import '../parser/parser.dart' show FormalParameterType;
+import '../scanner/token.dart' show BeginGroupToken, Token;
 import 'package:kernel/ast.dart' show AsyncMarker;
 
 import '../errors.dart' show internalError;
@@ -1174,7 +1172,8 @@ class AstBuilder extends ScopeListener {
     // TODO(paulberry): capture doc comments.  See dartbug.com/28851.
     Comment comment = null;
     Token period;
-    void unnamedConstructor(SimpleIdentifier returnType, SimpleIdentifier name) {
+    void unnamedConstructor(
+        SimpleIdentifier returnType, SimpleIdentifier name) {
       push(ast.constructorDeclaration(
           comment,
           metadata,