Not for review - Rebase of crrev.com/62833003

Source/core/rendering/compositing/CompositedLayerMapping.cpp

Index: Source/core/rendering/compositing/CompositedLayerMapping.cpp
diff --git a/Source/core/rendering/compositing/CompositedLayerMapping.cpp b/Source/core/rendering/compositing/CompositedLayerMapping.cpp
index 04cb0730eb44602305361513195a908f0dda7564..c05957f18610608b579ce79992b2ff022236de71 100644
--- a/Source/core/rendering/compositing/CompositedLayerMapping.cpp
+++ b/Source/core/rendering/compositing/CompositedLayerMapping.cpp
@@ -802,6 +802,8 @@ void CompositedLayerMapping::updateOverflowControlsHostLayerGeometry(const Rende
             m_owningLayer.renderer()->mapLocalToContainer(compositingStackingContext->renderer(), transformState, ApplyContainerFlip);
             transformState.flatten();
             LayoutPoint offsetFromStackingContainer = LayoutPoint(transformState.lastPlanarPoint());
+            if (RenderLayerScrollableArea* scrollableArea = compositingStackingContext->scrollableArea())
+                offsetFromStackingContainer.move(LayoutSize(scrollableArea->adjustedScrollOffset()));
             m_overflowControlsHostLayer->setPosition(FloatPoint(offsetFromStackingContainer));
         }
     } else {
@@ -1158,6 +1160,31 @@ void CompositedLayerMapping::updateScrollingBlockSelection()
     m_scrollingBlockSelectionLayer->setOffsetFromRenderer(toIntSize(blockSelectionGapsBounds.location()), GraphicsLayer::SetNeedsDisplay);
 }
 
+void CompositedLayerMapping::unbindAnimatedProperties()
+{
+    TRACE_EVENT0("teleport", "CompositedLayerMapping::unbindAnimatedProperties");
+    m_graphicsLayer->clearAnimatedProperties();
+    if (m_scrollingContentsLayer)
+        m_scrollingContentsLayer->clearAnimatedProperties();
+}
+
+void CompositedLayerMapping::bindAnimatedProperties(const Vector<String>& properties)
+{
+    TRACE_EVENT0("teleport", "CompositedLayerMapping::bindAnimatedProperties");
+    for (size_t i = 0; i < properties.size(); ++i) {
+        const String& property = properties[i];
+        // TODO(vollick): this seems to be repeated a bunch. Can it be consolidated?
+        Vector<String> components;
+        property.split(":", components);
+        if (components[1] == "scrollTop" || components[1] == "pendingScrollDelta") {
+            if (m_scrollingContentsLayer)
+                m_scrollingContentsLayer->addAnimatedProperty(property);
+        } else {
+            m_graphicsLayer->addAnimatedProperty(property);
+        }
+    }
+}
+
 void CompositedLayerMapping::updateDrawsContent()
 {
     bool hasPaintedContent = containsPaintedContent();