Don't implicitly run "pub get".

test/build/cleans_entire_build_directory_test.dart

 // Copyright (c) 2014, 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.
 
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 
 main() {
   integration("cleans entire build directory before a build", () {
     d.dir(appPath, [
       d.appPubspec(),
       d.dir('example', [
         d.file('file.txt', 'example')
       ]),
       d.dir('test', [
         d.file('file.txt', 'test')
       ])
     ]).create();
 
+    pubGet();
+
     // Make a build directory containing "example".
     schedulePub(args: ["build", "example"],
         output: new RegExp(r'Built 1 file to "build".'));
 
     // Now build again with just "test". Should wipe out "example".
     schedulePub(args: ["build", "test"],
         output: new RegExp(r'Built 1 file to "build".'));
 
     d.dir(appPath, [
       d.dir('build', [
         d.nothing('example'),
         d.dir('test', [
           d.file('file.txt', 'test')
         ]),
       ])
     ]).validate();
   });
 }