Move all main methods to tool/.

pkg/front_end/test/subpackage_relationships_test.dart

Index: pkg/front_end/test/subpackage_relationships_test.dart
diff --git a/pkg/front_end/test/subpackage_relationships_test.dart b/pkg/front_end/test/subpackage_relationships_test.dart
index 3386150e1ad14f8a47838b4595c9df9a7faf4471..ba82d6b3b23b280301db3e48aeab80c2d2815afa 100644
--- a/pkg/front_end/test/subpackage_relationships_test.dart
+++ b/pkg/front_end/test/subpackage_relationships_test.dart
@@ -52,9 +52,6 @@ final subpackageRules = {
     'lib/src/fasta/scanner',
     'lib/src/fasta/source',
   ]),
-  'lib/src/fasta/bin': new SubpackageRules(allowedDependencies: [
-    'lib/src/fasta',
-  ]),
   'lib/src/fasta/builder': new SubpackageRules(allowedDependencies: [
     'lib/src/fasta',
     'lib/src/fasta/dill',
@@ -102,6 +99,7 @@ final subpackageRules = {
     'lib/src/fasta/dill',
     'lib/src/fasta/kernel',
     'lib/src/fasta/analyzer',
+    'lib/src/fasta/scanner',
   ]),
   'lib/src/fasta/util': new SubpackageRules(),
   'lib/src/scanner': new SubpackageRules(allowedDependencies: [