Clean up remaining uses of WebCore namespace

Source/core/editing/FrameSelectionTest.cpp

 // Copyright 2014 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 "core/editing/FrameSelection.h"
 
 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "core/dom/Text.h"
 #include "core/html/HTMLBodyElement.h"
 #include "core/html/HTMLDocument.h"
 #include "core/testing/DummyPageHolder.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefPtr.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/testing/WTFTestHelpers.h"
 #include <gtest/gtest.h>
 
-using namespace WebCore;
+using namespace blink;
 
 namespace {
 
 class FrameSelectionTest : public ::testing::Test {
 protected:
     virtual void SetUp() OVERRIDE;
 
     HTMLDocument& document() const;
     void setSelection(const VisibleSelection&);
     const FrameSelection& selection() const;
@@ skipping 50 matching lines @@
     // Create a new VisibleSelection for the new document without frame and
     // update FrameSelection with the selection.
     VisibleSelection invalidSelection;
     invalidSelection.setWithoutValidation(Position(anotherText, 0), Position(anotherText, 5));
     setSelection(invalidSelection);
 
     EXPECT_TRUE(selection().isNone());
 }
 
 }