Fix selection invalidation in composited scrollers.

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 1274 matching lines @@
 inline void LayoutObject::invalidateSelectionIfNeeded(const LayoutBoxModelObject& paintInvalidationContainer, PaintInvalidationReason invalidationReason)
 {
     // Update selection rect when we are doing full invalidation (in case that the object is moved, composite status changed, etc.)
     // or shouldInvalidationSelection is set (in case that the selection itself changed).
     bool fullInvalidation = view()->doingFullPaintInvalidation() || isFullPaintInvalidationReason(invalidationReason);
     if (!fullInvalidation && !shouldInvalidateSelection())
         return;
 
     LayoutRect oldSelectionRect = previousSelectionRectForPaintInvalidation();
     LayoutRect newSelectionRect = selectionRectForPaintInvalidation(&paintInvalidationContainer);
+
+    // 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());
+        newSelectionRect.move(inverseOffset);
+    }
+
     setPreviousSelectionRectForPaintInvalidation(newSelectionRect);
 
     if (RuntimeEnabledFeatures::slimmingPaintEnabled() && shouldInvalidateSelection())
         invalidateDisplayItemClients(paintInvalidationContainer);
 
     if (fullInvalidation)
         return;
 
     fullyInvalidatePaint(paintInvalidationContainer, PaintInvalidationSelection, oldSelectionRect, newSelectionRect);
 }
@@ skipping 58 matching lines @@
 
     if (RuntimeEnabledFeatures::slimmingPaintEnabled())
         invalidateDisplayItemClients(paintInvalidationContainer);
 
     if (invalidationReason == PaintInvalidationIncremental) {
         incrementallyInvalidatePaint(paintInvalidationContainer, oldBounds, newBounds, newLocation);
         return invalidationReason;
     }
 
     fullyInvalidatePaint(paintInvalidationContainer, invalidationReason, oldBounds, newBounds);
+
     return invalidationReason;
 }
 
 PaintInvalidationReason LayoutObject::paintInvalidationReason(const LayoutBoxModelObject& paintInvalidationContainer,
     const LayoutRect& oldBounds, const LayoutPoint& oldPositionFromPaintInvalidationBacking,
     const LayoutRect& newBounds, const LayoutPoint& newPositionFromPaintInvalidationBacking) const
 {
     // First check for InvalidationLocationChange to avoid it from being hidden by other
     // invalidation reasons because we'll need to force check for paint invalidation for
     // children when location of this object changed.
@@ skipping 2001 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