Clean up remaining uses of WebCore namespace

Source/core/dom/DOMPointReadOnly.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/dom/DOMPointReadOnly.h"
 
-namespace WebCore {
+namespace blink {
 
 DOMPointReadOnly* DOMPointReadOnly::create(double x, double y, double z, double w)
 {
     return new DOMPointReadOnly(x, y, z, w);
 }
 
 DOMPointReadOnly::DOMPointReadOnly(double x, double y, double z, double w)
     : m_x(x)
     , m_y(y)
     , m_z(z)
     , m_w(w)
 {
 }
 
-} // namespace WebCore
+} // namespace blink