Remove package imports from itself.

pkg/front_end/lib/src/fasta/source/source_loader.dart

Index: pkg/front_end/lib/src/fasta/source/source_loader.dart
diff --git a/pkg/front_end/lib/src/fasta/source/source_loader.dart b/pkg/front_end/lib/src/fasta/source/source_loader.dart
index e8c9a14780861ae7a3b2ab99387edd350c39382b..3df02d01a4591f01cbbb0ee54fad3bc1974db98d 100644
--- a/pkg/front_end/lib/src/fasta/source/source_loader.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_loader.dart
@@ -8,13 +8,11 @@ import 'dart:async' show Future;
 
 import 'dart:io' show FileSystemException;
 
-import 'package:front_end/src/fasta/scanner/io.dart' show readBytesFromFile;
+import '../scanner/io.dart' show readBytesFromFile;
 
-import 'package:front_end/src/fasta/scanner.dart'
-    show ErrorToken, ScannerResult, Token, scan;
+import '../scanner.dart' show ErrorToken, ScannerResult, Token, scan;
 
-import 'package:front_end/src/fasta/parser/class_member_parser.dart'
-    show ClassMemberParser;
+import '../parser/class_member_parser.dart' show ClassMemberParser;
 
 import 'package:kernel/ast.dart' show Program;