Remove dependency on m_previousPositionFromPaintInvalidationBacking for spv2

Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1318 matching lines @@
     fullyInvalidatePaint(paintInvalidationContainer, PaintInvalidationSelection, oldSelectionRect, newSelectionRect);
 }
 
 PaintInvalidationReason LayoutObject::invalidatePaintIfNeeded(PaintInvalidationState& paintInvalidationState, const LayoutBoxModelObject& paintInvalidationContainer)
 {
     LayoutView* v = view();
     if (v->document().printing())
         return PaintInvalidationNone; // Don't invalidate paints if we're printing.
 
     const LayoutRect oldBounds = previousPaintInvalidationRect();
-    const LayoutPoint oldLocation = previousPositionFromPaintInvalidationBacking();
+    const LayoutPoint oldLocation = RuntimeEnabledFeatures::slimmingPaintV2Enabled() ? LayoutPoint() : previousPositionFromPaintInvalidationBacking();
     LayoutRect newBounds = boundsRectForPaintInvalidation(&paintInvalidationContainer, &paintInvalidationState);
-    LayoutPoint newLocation = DeprecatedPaintLayer::positionFromPaintInvalidationBacking(this, &paintInvalidationContainer, &paintInvalidationState);
+    LayoutPoint newLocation = RuntimeEnabledFeatures::slimmingPaintV2Enabled() ? LayoutPoint() : DeprecatedPaintLayer::positionFromPaintInvalidationBacking(this, &paintInvalidationContainer, &paintInvalidationState);
 
     // Composited scrolling should not be included in the bounds and position tracking, because the graphics layer backing the scroller
     // does not move on scroll.
     if (paintInvalidationContainer.usesCompositedScrolling() && &paintInvalidationContainer != this) {
         LayoutSize inverseOffset(toLayoutBox(&paintInvalidationContainer)->scrolledContentOffset());
         newLocation.move(inverseOffset);
         newBounds.move(inverseOffset);
     }
 
     setPreviousPaintInvalidationRect(newBounds);
-    setPreviousPositionFromPaintInvalidationBacking(newLocation);
+    if (!RuntimeEnabledFeatures::slimmingPaintV2Enabled())
+        setPreviousPositionFromPaintInvalidationBacking(newLocation);
 
     PaintInvalidationReason invalidationReason = paintInvalidationReason(paintInvalidationContainer, oldBounds, oldLocation, newBounds, newLocation);
 
     // We need to invalidate the selection before checking for whether we are doing a full invalidation.
     // This is because we need to update the old rect regardless.
     invalidateSelectionIfNeeded(paintInvalidationContainer, invalidationReason);
 
     TRACE_EVENT2(TRACE_DISABLED_BY_DEFAULT("blink.invalidation"), "LayoutObject::invalidatePaintIfNeeded()",
         "object", this->debugName().ascii(),
         "info", jsonObjectForOldAndNewRects(oldBounds, oldLocation, newBounds, newLocation));
@@ skipping 1761 matching lines @@
         return PaintInvalidationForcedByLayout;
     case DocumentLifecycle::InCompositingUpdate:
         return PaintInvalidationCompositingUpdate;
     default:
         return PaintInvalidationFull;
     }
 }
 
 inline void LayoutObject::markContainerChainForPaintInvalidation()
 {
+    // Setting layer-needs-repaint doesn't mean we'll fully repaint the layer, but
+    // means we won't skip painting of the whole layer with a CachedSubsequenceDisplayItem.
+    // This is to ensure we'll check paint offset changes of the objects on the layer.
+    // We'll still use cached display items for non-invalidated objects on the layer.
+    if (RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
+        if (DeprecatedPaintLayer* enclosingLayer = this->enclosingLayer())
+            enclosingLayer->setNeedsRepaint();
+    }
+
     for (LayoutObject* container = this->containerCrossingFrameBoundaries(); container && !container->shouldCheckForPaintInvalidationRegardlessOfPaintInvalidationState(); container = container->containerCrossingFrameBoundaries())
         container->m_bitfields.setChildShouldCheckForPaintInvalidation(true);
 }
 
 void LayoutObject::setShouldInvalidateSelection()
 {
     if (!canUpdateSelectionOnRootLineBoxes())
         return;
 
     m_bitfields.setShouldInvalidateSelection(true);
@@ skipping 235 matching lines @@
         const blink::LayoutObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
     } else {
         fprintf(stderr, "Cannot showLayoutTree. Root is (nil)\n");
     }
 }
 
 #endif