cc: Remove forbidden using namespace directives.

cc/layer_iterator_unittest.cc

Index: cc/layer_iterator_unittest.cc
diff --git a/cc/layer_iterator_unittest.cc b/cc/layer_iterator_unittest.cc
index 74e7a3eb7adf224005c5484e60be2395dc923e98..55124e20249e67b0d300c2b14a127213198e85a1 100644
--- a/cc/layer_iterator_unittest.cc
+++ b/cc/layer_iterator_unittest.cc
@@ -12,13 +12,13 @@
 #include "testing/gtest/include/gtest/gtest.h"
 #include <public/WebTransformationMatrix.h>
 
-using namespace cc;
 using WebKit::WebTransformationMatrix;
 using ::testing::Mock;
 using ::testing::_;
 using ::testing::AtLeast;
 using ::testing::AnyNumber;
 
+namespace cc {
 namespace {
 
 class TestLayer : public Layer {
@@ -252,4 +252,5 @@ TEST(LayerIteratorTest, complexTreeMultiSurface)
     EXPECT_COUNT(root3, -1, -1, 0);
 }
 
-}  // anonymous namespace
+}  // namespace
+}  // namespace cc