Convert pkg/http to use "package:" imports.

pkg/http/test/multipart_test.dart

Index: pkg/http/test/multipart_test.dart
diff --git a/pkg/http/test/multipart_test.dart b/pkg/http/test/multipart_test.dart
index 136dfa06b17aceda9e7190a897a93ff9a4b0292a..abbd5094d3a80f3e64408865c8a0c53d1cb1f890 100644
--- a/pkg/http/test/multipart_test.dart
+++ b/pkg/http/test/multipart_test.dart
@@ -9,10 +9,9 @@ import 'dart:utf';
 
 // TODO(nweiz): get rid of this import before packaging this
 import '../../../tests/utils/test_utils.dart';
-// TODO(nweiz): make these package: imports
-import '../../unittest/lib/unittest.dart';
-import '../lib/http.dart' as http;
-import '../lib/src/utils.dart';
+import 'package:unittest/unittest.dart';
+import 'package:http/http.dart' as http;
+import 'package:http/src/utils.dart';
 
 import 'utils.dart';
 
@@ -183,7 +182,7 @@ void main() {
         content-type: application/octet-stream
         content-disposition: form-data; name="file"
 
-        
+
         --{{boundary}}--
         '''));
   });