Merge 139461

Source/WebCore/rendering/RenderLayer.cpp

Index: Source/WebCore/rendering/RenderLayer.cpp
===================================================================
--- Source/WebCore/rendering/RenderLayer.cpp	(revision 139983)
+++ Source/WebCore/rendering/RenderLayer.cpp	(working copy)
@@ -166,6 +166,7 @@
 #if USE(ACCELERATED_COMPOSITING)
     , m_hasCompositingDescendant(false)
     , m_indirectCompositingReason(NoIndirectCompositingReason)
+    , m_viewportConstrainedNotCompositedReason(NoNotCompositedReason)
 #endif
     , m_containsDirtyOverlayScrollbars(false)
     , m_updatingMarqueePosition(false)
@@ -3397,8 +3398,8 @@
             // If this RenderLayer should paint into its backing, that will be done via RenderLayerBacking::paintIntoLayer().
             return;
         }
-    } else if (compositor()->fixedPositionLayerNotCompositedReason(this) == RenderLayerCompositor::LayerBoundsOutOfView) {
-        // Don't paint out-of-view fixed position layers (when doing prepainting) because they will never be visible
+    } else if (viewportConstrainedNotCompositedReason() == NotCompositedForBoundsOutOfView) {
+        // Don't paint out-of-view viewport constrained layers (when doing prepainting) because they will never be visible
         // unless their position or viewport size is changed.
         return;
     }