Move shell service to toplevel shell namespace

components/leveldb/leveldb_service_unittest.cc

Index: components/leveldb/leveldb_service_unittest.cc
diff --git a/components/leveldb/leveldb_service_unittest.cc b/components/leveldb/leveldb_service_unittest.cc
index 6acd0f8579c80d401b5c7bde9c49416fbaf5e6d5..785478b641a9de9311a9d20e2042a5ff110db615 100644
--- a/components/leveldb/leveldb_service_unittest.cc
+++ b/components/leveldb/leveldb_service_unittest.cc
@@ -19,7 +19,7 @@ using mojo::Capture;
 namespace leveldb {
 namespace {
 
-class LevelDBServiceTest : public mojo::test::ShellTest {
+class LevelDBServiceTest : public shell::test::ShellTest {
  public:
   LevelDBServiceTest() : ShellTest("exe:leveldb_service_unittests") {}
   ~LevelDBServiceTest() override {}