Fix unit test style in Source/platform/, part 1.

Source/platform/geometry/FloatSizeTest.cpp

 // 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 "config.h"
 #include "platform/geometry/FloatSize.h"
 
 #include "platform/geometry/GeometryTestHelpers.h"
-
 #include <gtest/gtest.h>
 
-using namespace blink;
-
-namespace {
+namespace blink {
 
 TEST(FloatSizeTest, DiagonalLengthTest)
 {
     // Sanity check the Pythagorean triples 3-4-5 and 5-12-13
     FloatSize s1 = FloatSize(3.f, 4.f);
     EXPECT_PRED_FORMAT2(GeometryTest::AssertAlmostEqual, s1.diagonalLength(), 5.f);
     FloatSize s2 = FloatSize(5.f, 12.f);
     EXPECT_PRED_FORMAT2(GeometryTest::AssertAlmostEqual, s2.diagonalLength(), 13.f);
 
     // Test very small numbers.
     FloatSize s3 = FloatSize(.5e-20f, .5e-20f);
     EXPECT_PRED_FORMAT2(GeometryTest::AssertAlmostEqual, s3.diagonalLength(), .707106781186548e-20f);
 
     // Test very large numbers.
     FloatSize s4 = FloatSize(.5e20f, .5e20f);
     EXPECT_PRED_FORMAT2(GeometryTest::AssertAlmostEqual, s4.diagonalLength(), .707106781186548e20f);
 }
 
-}
+} // namespace blink