First pass at removing position:fixed.

sky/engine/core/rendering/RenderLayerModelObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010, 2012 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 53 matching lines @@
     return m_layer && m_layer->isSelfPaintingLayer();
 }
 
 ScrollableArea* RenderLayerModelObject::scrollableArea() const
 {
     return m_layer ? m_layer->scrollableArea() : 0;
 }
 
 void RenderLayerModelObject::willBeDestroyed()
 {
-    if (isPositioned()) {
-        // Don't use this->view() because the document's renderView has been set to 0 during destruction.
-        if (LocalFrame* frame = this->frame()) {
-            if (FrameView* frameView = frame->view()) {
-                if (style()->hasViewportConstrainedPosition())
-                    frameView->removeViewportConstrainedObject(this);
-            }
-        }
-    }
-
     RenderObject::willBeDestroyed();
-
     destroyLayer();
 }
 
 void RenderLayerModelObject::styleWillChange(StyleDifference diff, const RenderStyle& newStyle)
 {
     s_wasFloating = isFloating();
 
     if (RenderStyle* oldStyle = style()) {
         if (parent() && diff.needsPaintInvalidationLayer()) {
             if (oldStyle->hasAutoClip() != newStyle.hasAutoClip()
@@ skipping 34 matching lines @@
         if (hadTransform)
             setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation();
     }
 
     if (layer()) {
         // FIXME: Ideally we shouldn't need this setter but we can't easily infer an overflow-only layer
         // from the style.
         layer()->setLayerType(type);
         layer()->styleChanged(diff, oldStyle);
     }
-
-    if (FrameView *frameView = view()->frameView()) {
-        bool newStyleIsViewportConstained = style()->hasViewportConstrainedPosition();
-        bool oldStyleIsViewportConstrained = oldStyle && oldStyle->hasViewportConstrainedPosition();
-        if (newStyleIsViewportConstained != oldStyleIsViewportConstrained) {
-            if (newStyleIsViewportConstained && layer())
-                frameView->addViewportConstrainedObject(this);
-            else
-                frameView->removeViewportConstrainedObject(this);
-        }
-    }
 }
 
 void RenderLayerModelObject::addLayerHitTestRects(LayerHitTestRects& rects, const RenderLayer* currentLayer, const LayoutPoint& layerOffset, const LayoutRect& containerRect) const
 {
     if (hasLayer()) {
         if (isRenderView()) {
             // RenderView is handled with a special fast-path, but it needs to know the current layer.
             RenderObject::addLayerHitTestRects(rects, layer(), LayoutPoint(), LayoutRect());
         } else {
             // Since a RenderObject never lives outside it's container RenderLayer, we can switch
@@ skipping 38 matching lines @@
     InvalidationReason reason = invalidatePaintIfNeeded(paintInvalidationState, newPaintInvalidationContainer);
 
     PaintInvalidationState childTreeWalkState(paintInvalidationState, *this, newPaintInvalidationContainer);
     if (reason == InvalidationLocationChange || reason == InvalidationFull)
         childTreeWalkState.setForceCheckForPaintInvalidation();
     RenderObject::invalidateTreeIfNeeded(childTreeWalkState);
 }
 
 } // namespace blink