cc: Remove forbidden using namespace directives.

cc/layer_tree_host_impl_unittest.cc

Index: cc/layer_tree_host_impl_unittest.cc
diff --git a/cc/layer_tree_host_impl_unittest.cc b/cc/layer_tree_host_impl_unittest.cc
index ed7ef131e5a47c07e363352f50905def8c937cf5..78b750fae250fd802a4331aa3a960deb5b3af283 100644
--- a/cc/layer_tree_host_impl_unittest.cc
+++ b/cc/layer_tree_host_impl_unittest.cc
@@ -49,7 +49,6 @@
 #include <public/WebVideoFrame.h>
 #include <public/WebVideoFrameProvider.h>
 
-using namespace cc;
 using namespace LayerTestCommon;
 using namespace WebKit;
 using namespace WebKitTests;
@@ -61,6 +60,7 @@ using ::testing::AnyNumber;
 using ::testing::AtLeast;
 using ::testing::_;
 
+namespace cc {
 namespace {
 
 // This test is parametrized to run all tests with the
@@ -4422,4 +4422,5 @@ INSTANTIATE_TEST_CASE_P(LayerTreeHostImplTests,
                         LayerTreeHostImplTest,
                         ::testing::Values(false, true));
 
-}  // anonymous namespace
+}  // namespace
+}  // namespace cc