Fix analyzer hints and warnings in test/.

test/global/activate/activate_hosted_after_git_test.dart

Index: test/global/activate/activate_hosted_after_git_test.dart
diff --git a/test/global/activate/activate_hosted_after_git_test.dart b/test/global/activate/activate_hosted_after_git_test.dart
index 514aaf57336735943917254fad46bc496fe05da6..50e1c8d4b03233e30ecfca044146b037c17e229d 100644
--- a/test/global/activate/activate_hosted_after_git_test.dart
+++ b/test/global/activate/activate_hosted_after_git_test.dart
@@ -2,7 +2,6 @@
 // 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 'package:path/path.dart' as p;
 import 'package:pub/src/io.dart';
 
 import '../../descriptor.dart' as d;
@@ -27,7 +26,6 @@ main() {
 
     schedulePub(args: ["global", "activate", "-sgit", "../foo.git"]);
 
-    var path = canonicalize(p.join(sandboxDir, "foo"));
     schedulePub(args: ["global", "activate", "foo"], output: """
         Package foo is currently active from Git repository "../foo.git".
         Resolving dependencies...