core/loader: create private directory to store private classes

third_party/WebKit/Source/core/loader/private/FrameClientHintsPreferencesContext.cpp

 // Copyright 2016 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 "core/loader/FrameClientHintsPreferencesContext.h"
+#include "core/loader/private/FrameClientHintsPreferencesContext.h"
 
 #include "core/frame/UseCounter.h"
 
 namespace blink {
 
 FrameClientHintsPreferencesContext::FrameClientHintsPreferencesContext(
     Frame* frame)
     : m_frame(frame) {}
 
 void FrameClientHintsPreferencesContext::countClientHintsDPR() {
   UseCounter::count(m_frame, UseCounter::ClientHintsDPR);
 }
 
 void FrameClientHintsPreferencesContext::countClientHintsResourceWidth() {
   UseCounter::count(m_frame, UseCounter::ClientHintsResourceWidth);
 }
 
 void FrameClientHintsPreferencesContext::countClientHintsViewportWidth() {
   UseCounter::count(m_frame, UseCounter::ClientHintsViewportWidth);
 }
 
 }  // namespace blink