Revert "Adapt and reland old position sticky implementation from https://codereview.chromium.org/34…

third_party/WebKit/Source/core/layout/compositing/CompositingInputsUpdater.cpp

Index: third_party/WebKit/Source/core/layout/compositing/CompositingInputsUpdater.cpp
diff --git a/third_party/WebKit/Source/core/layout/compositing/CompositingInputsUpdater.cpp b/third_party/WebKit/Source/core/layout/compositing/CompositingInputsUpdater.cpp
index e8beec30ee0016712a5ea119191d3414a64d16ec..e94f3ec8911803f061737fb1dce147b7e788a518 100644
--- a/third_party/WebKit/Source/core/layout/compositing/CompositingInputsUpdater.cpp
+++ b/third_party/WebKit/Source/core/layout/compositing/CompositingInputsUpdater.cpp
@@ -4,9 +4,7 @@
 
 #include "core/layout/compositing/CompositingInputsUpdater.h"
 
-#include "core/frame/FrameView.h"
 #include "core/layout/LayoutBlock.h"
-#include "core/layout/LayoutView.h"
 #include "core/layout/compositing/CompositedLayerMapping.h"
 #include "core/layout/compositing/PaintLayerCompositor.h"
 #include "core/paint/PaintLayer.h"
@@ -99,28 +97,6 @@ void CompositingInputsUpdater::updateRecursive(PaintLayer* layer, UpdateType upd
     if (!layer->childNeedsCompositingInputsUpdate() && updateType != ForceUpdate)
         return;
 
-    const PaintLayer* previousOverflowLayer = layer->ancestorOverflowLayer();
-    layer->updateAncestorOverflowLayer(info.lastOverflowClipLayer);
-    if (info.lastOverflowClipLayer && layer->needsCompositingInputsUpdate() && layer->layoutObject()->style()->position() == StickyPosition) {
-        if (info.lastOverflowClipLayer != previousOverflowLayer) {
-            // Old ancestor scroller should no longer have these constraints.
-            ASSERT(!previousOverflowLayer || !previousOverflowLayer->getScrollableArea()->stickyConstraintsMap().contains(layer));
-
-            if (info.lastOverflowClipLayer->isRootLayer())
-                layer->layoutObject()->view()->frameView()->addViewportConstrainedObject(layer->layoutObject());
-            else if (previousOverflowLayer && previousOverflowLayer->isRootLayer())
-                layer->layoutObject()->view()->frameView()->removeViewportConstrainedObject(layer->layoutObject());
-        }
-        layer->layoutObject()->updateStickyPositionConstraints();
-
-        // Sticky position constraints and ancestor overflow scroller affect
-        // the sticky layer position, so we need to update it again here.
-        // TODO(flackr): This should be refactored in the future to be clearer
-        // (i.e. update layer position and ancestor inputs updates in the
-        // same walk)
-        layer->updateLayerPosition();
-    }
-
     m_geometryMap.pushMappingsToAncestor(layer, layer->parent());
 
     if (layer->hasCompositedLayerMapping())
@@ -187,9 +163,6 @@ void CompositingInputsUpdater::updateRecursive(PaintLayer* layer, UpdateType upd
     if (layer->stackingNode()->isStackingContext())
         info.ancestorStackingContext = layer;
 
-    if (layer->isRootLayer() || layer->layoutObject()->hasOverflowClip())
-        info.lastOverflowClipLayer = layer;
-
     if (layer->scrollsOverflow())
         info.lastScrollingAncestor = layer;