Convert the small packages in pkg to use "package:".

pkg/args/test/args_test.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library args_test;
 
-import '../../../pkg/unittest/lib/unittest.dart';
-
+import 'package:unittest/unittest.dart';
 import 'package:args/args.dart';
 
 main() {
   group('ArgParser.addFlag()', () {
     test('throws ArgumentError if the flag already exists', () {
       var parser = new ArgParser();
       parser.addFlag('foo');
       throwsIllegalArg(() => parser.addFlag('foo'));
     });
 
@@ skipping 162 matching lines @@
       });
 
       test('are invoked even if the option is not present', () {
         var a = 'not called';
         var parser = new ArgParser();
         parser.addOption('a', callback: (value) => a = value);
 
         var args = parser.parse([]);
         expect(a, isNull);
       });
-      
+
       test('for multiple present, allowMultiple, options are invoked with '
            'value as a list', () {
         var a;
         var parser = new ArgParser();
-        parser.addOption('a', allowMultiple: true, 
+        parser.addOption('a', allowMultiple: true,
             callback: (value) => a = value);
-          
+
         var args = parser.parse(['--a=v', '--a=x']);
         expect(a, equals(['v', 'x']));
       });
-      
+
       test('for single present, allowMultiple, options are invoked with '
            ' value as a single element list', () {
         var a;
         var parser = new ArgParser();
         parser.addOption('a', allowMultiple: true,
             callback: (value) => a = value);
-        
+
         var args = parser.parse(['--a=v']);
         expect(a, equals(['v']));
       });
-      
+
       test('for absent, allowMultiple, options are invoked with default '
            'value as a list.', () {
         var a;
         var parser = new ArgParser();
         parser.addOption('a', allowMultiple: true, defaultsTo: 'v',
             callback: (value) => a = value);
-        
+
         var args = parser.parse([]);
         expect(a, equals(['v']));
       });
-      
+
       test('for absent, allowMultiple, options are invoked with value '
            'as an empty list.', () {
         var a;
         var parser = new ArgParser();
         parser.addOption('a', allowMultiple: true,
             callback: (value) => a = value);
-        
+
         var args = parser.parse([]);
         expect(a, isEmpty);
       });
     });
 
     group('abbreviations', () {
       test('are parsed with a preceding "-"', () {
         var parser = new ArgParser();
         parser.addFlag('arg', abbr: 'a');
 
@@ skipping 460 matching lines @@
         throw new ArgumentError(
             'Line "$line" does not have enough indentation.');
       }
 
       lines[i] = line.substring(indent);
     }
   }
 
   return Strings.join(lines, '\n');
 }