Update clang, re-enable checker, fix issues it flags

services/files/c/tests/mojio_test_base.cc

Index: services/files/c/tests/mojio_test_base.cc
diff --git a/services/files/c/tests/mojio_test_base.cc b/services/files/c/tests/mojio_test_base.cc
new file mode 100644
index 0000000000000000000000000000000000000000..d3a6b57e2f69f11d9a03bb35883a3758b07004ff
--- /dev/null
+++ b/services/files/c/tests/mojio_test_base.cc
@@ -0,0 +1,30 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "services/files/c/tests/mojio_test_base.h"
+
+namespace mojio {
+namespace test {
+
+void MojioTestBase::SetUp() {
+  MojioImplTestBase::SetUp();
+
+  // Explicitly set up the singletons.
+  MOJO_CHECK(singletons::GetErrnoImpl());
+  MOJO_CHECK(singletons::GetFDTable());
+  singletons::SetCurrentWorkingDirectory(directory().Pass());
+  MOJO_CHECK(singletons::GetCurrentWorkingDirectory());
+}
+
+void MojioTestBase::TearDown() {
+  // Explicitly tear down the singletons.
+  singletons::ResetCurrentWorkingDirectory();
+  singletons::ResetFDTable();
+  singletons::ResetErrnoImpl();
+
+  MojioImplTestBase::TearDown();
+}
+
+}  // namespace test
+}  // namespace mojio