cc: Remove forbidden using namespace directives.

cc/occlusion_tracker_unittest.cc

 // Copyright 2012 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 "config.h"
 
 #include "cc/occlusion_tracker.h"
 
 #include "cc/layer.h"
 #include "cc/layer_animation_controller.h"
 #include "cc/layer_impl.h"
 #include "cc/layer_tree_host_common.h"
 #include "cc/math_util.h"
 #include "cc/overdraw_metrics.h"
 #include "cc/single_thread_proxy.h"
 #include "cc/test/animation_test_common.h"
 #include "cc/test/geometry_test_utils.h"
 #include "cc/test/occlusion_tracker_test_common.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include <public/WebFilterOperation.h>
 #include <public/WebFilterOperations.h>
 #include <public/WebTransformationMatrix.h>
 
-using namespace cc;
 using namespace WebKit;
 using namespace WebKitTests;
 
+namespace cc {
 namespace {
 
 class TestContentLayer : public Layer {
 public:
     TestContentLayer()
         : Layer()
         , m_overrideOpaqueContentsRect(false)
     {
     }
 
@@ skipping 3033 matching lines @@
         // The large layer is tracked as it is large enough.
         this->visitLayer(large, occlusion);
 
         EXPECT_EQ(gfx::Rect(gfx::Point(), trackingSize).ToString(), occlusion.occlusionInScreenSpace().ToString());
         EXPECT_EQ(gfx::Rect(gfx::Point(), trackingSize).ToString(), occlusion.occlusionInTargetSurface().ToString());
     }
 };
 
 ALL_OCCLUSIONTRACKER_TEST(OcclusionTrackerTestMinimumTrackingSize);
 
-}  // anonymous namespace
+}  // namespace
+}  // namespace cc