Remove BackForwardClient, cleanup starting a history navigation

Source/core/frame/History.cpp

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 16 matching lines @@
 #include "core/frame/History.h"
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/frame/LocalFrame.h"
 #include "core/loader/DocumentLoader.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/loader/HistoryItem.h"
-#include "core/page/BackForwardClient.h"
 #include "core/page/Page.h"
 #include "platform/weborigin/KURL.h"
 #include "platform/weborigin/SecurityOrigin.h"
 #include "wtf/MainThread.h"
 
 namespace blink {
 
 History::History(LocalFrame* frame)
     : DOMWindowProperty(frame)
     , m_lastStateObjectRequested(nullptr)
 {
 }
 
 void History::trace(Visitor* visitor)
 {
     DOMWindowProperty::trace(visitor);
 }
 
 unsigned History::length() const
 {
-    if (!m_frame)
+    if (!m_frame || !m_frame->loader().client())
         return 0;
-    if (!m_frame->page())
-        return 0;
-    return m_frame->page()->backForward().backForwardListCount();
+    return m_frame->loader().client()->backForwardLength();
 }
 
 SerializedScriptValue* History::state()
 {
     m_lastStateObjectRequested = stateInternal();
     return m_lastStateObjectRequested.get();
 }
 
 SerializedScriptValue* History::stateInternal() const
 {
@@ skipping 21 matching lines @@
     go(context, -1);
 }
 
 void History::forward(ExecutionContext* context)
 {
     go(context, 1);
 }
 
 void History::go(ExecutionContext* context, int distance)
 {
-    if (!m_frame)
+    if (!m_frame || !m_frame->loader().client())
         return;
 
     ASSERT(isMainThread());
     Document* activeDocument = toDocument(context);
     if (!activeDocument)
         return;
 
     if (!activeDocument->canNavigate(*m_frame))
         return;
 
-    m_frame->navigationScheduler().scheduleHistoryNavigation(distance);
+    if (distance)
+        m_frame->loader().client()->navigateBackForward(distance);
+    else
+        m_frame->navigationScheduler().scheduleReload();
 }
 
 KURL History::urlForState(const String& urlString)
 {
     Document* document = m_frame->document();
 
     if (urlString.isNull())
         return document->url();
     if (urlString.isEmpty())
         return document->baseURL();
 
     return KURL(document->baseURL(), urlString);
 }
 
 void History::stateObjectAdded(PassRefPtr<SerializedScriptValue> data, const String& /* title */, const String& urlString, FrameLoadType type, ExceptionState& exceptionState)
 {
     if (!m_frame || !m_frame->page() || !m_frame->loader().documentLoader())
         return;
 
     KURL fullURL = urlForState(urlString);
     if (!fullURL.isValid() || !m_frame->document()->securityOrigin()->canRequest(fullURL)) {
         // We can safely expose the URL to JavaScript, as a) no redirection takes place: JavaScript already had this URL, b) JavaScript can only access a same-origin History object.
         exceptionState.throwSecurityError("A history state object with URL '" + fullURL.elidedString() + "' cannot be created in a document with origin '" + m_frame->document()->securityOrigin()->toString() + "'.");
         return;
     }
     m_frame->loader().updateForSameDocumentNavigation(fullURL, SameDocumentNavigationHistoryApi, data, type);
 }
 
 } // namespace blink