Cleanup ScrollableArea scrolling API

Source/core/loader/FrameLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) Research In Motion Limited 2009. All rights reserved.
  * Copyright (C) 2011 Kris Jordan <krisjordan@gmail.com>
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ skipping 1087 matching lines @@
         // If the pinch viewport's offset is (-1, -1) it means the history item
         // is an old version of HistoryItem so distribute the scroll between
         // the main frame and the pinch viewport as best as we can.
         if (pinchViewportOffset.x() == -1 && pinchViewportOffset.y() == -1)
             pinchViewportOffset = FloatPoint(frameScrollOffset - view->scrollPosition());
 
         m_frame->host()->pinchViewport().setLocation(pinchViewportOffset);
     } else {
         IntPoint adjustedScrollPosition = view->adjustScrollPositionWithinRange(m_currentItem->scrollPoint());
         if (adjustedScrollPosition != view->scrollPosition())
-            view->notifyScrollPositionChanged(adjustedScrollPosition);
+            view->setScrollPosition(adjustedScrollPosition, ProgrammaticScroll);
     }
 
     if (m_frame->isMainFrame()) {
         if (ScrollingCoordinator* scrollingCoordinator = m_frame->page()->scrollingCoordinator())
             scrollingCoordinator->frameViewRootLayerDidChange(view);
     }
     documentLoader()->initialScrollState().didRestoreFromHistory = true;
 }
 
 String FrameLoader::userAgent(const KURL& url) const
@@ skipping 356 matching lines @@
     // FIXME: We need a way to propagate insecure requests policy flags to
     // out-of-process frames. For now, we'll always use default behavior.
     if (!parentFrame->isLocalFrame())
         return nullptr;
 
     ASSERT(toLocalFrame(parentFrame)->document());
     return toLocalFrame(parentFrame)->document()->insecureNavigationsToUpgrade();
 }
 
 } // namespace blink