Merge 99752 - REGRESSION (r93614): Content remains despite parent element being scrolled off page...

Source/WebCore/rendering/RenderLayer.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 138 matching lines @@
     , m_visibleDescendantStatusDirty(false)
     , m_hasVisibleDescendant(false)
     , m_isPaginated(false)
     , m_3DTransformedDescendantStatusDirty(true)
     , m_has3DTransformedDescendant(false)
 #if USE(ACCELERATED_COMPOSITING)
     , m_hasCompositingDescendant(false)
     , m_mustOverlapCompositedLayers(false)
 #endif
     , m_containsDirtyOverlayScrollbars(false)
+    , m_canSkipRepaintRectsUpdateOnScroll(renderer->isTableCell())
     , m_renderer(renderer)
     , m_parent(0)
     , m_previous(0)
     , m_next(0)
     , m_first(0)
     , m_last(0)
     , m_posZOrderList(0)
     , m_negZOrderList(0)
     , m_normalFlowList(0)
     , m_clipRects(0)
@@ skipping 247 matching lines @@
 
 void RenderLayer::clearRepaintRects()
 {
     ASSERT(!m_hasVisibleContent);
     ASSERT(!m_visibleContentStatusDirty);
 
     m_repaintRect = IntRect();
     m_outlineBox = IntRect();
 }
 
-void RenderLayer::updateLayerPositionsAfterScroll(bool fixed)
+void RenderLayer::updateLayerPositionsAfterScroll(UpdateLayerPositionsAfterScrollFlags flags)
 {
     ASSERT(!m_visibleContentStatusDirty);
 
     // If we have no visible content, there is no point recomputing our rectangles as
     // they will be empty. If our visibility changes, we are expected to recompute all
     // our positions anyway.
     if (!m_hasVisibleContent)
         return;
 
     updateLayerPosition();
 
-    if (fixed || renderer()->style()->position() == FixedPosition) {
+    if ((flags & HasSeenFixedPositionedAncestor) || renderer()->style()->position() == FixedPosition) {
         // FIXME: Is it worth passing the offsetFromRoot around like in updateLayerPositions?
         computeRepaintRects();
-        fixed = true;
+        flags |= HasSeenFixedPositionedAncestor;
     } else if (renderer()->hasTransform() && !renderer()->isRenderView()) {
         // Transforms act as fixed position containers, so nothing inside a
         // transformed element can be fixed relative to the viewport if the
         // transformed element is not fixed itself or child of a fixed element.
         return;
+    } else if ((flags & HasSeenAncestorWithOverflowClip) && !m_canSkipRepaintRectsUpdateOnScroll) {
+        // If we have seen an overflow clip, we should update our repaint rects as clippedOverflowRectForRepaint
+        // intersects it with our ancestor overflow clip that may have moved.
+        computeRepaintRects();
     }
 
+    if (renderer()->hasOverflowClip())
+        flags |= HasSeenAncestorWithOverflowClip;
+
     for (RenderLayer* child = firstChild(); child; child = child->nextSibling())
-        child->updateLayerPositionsAfterScroll(fixed);
+        child->updateLayerPositionsAfterScroll(flags);
 
     // We don't update our reflection as scrolling is a translation which does not change the size()
     // of an object, thus RenderReplica will still repaint itself properly as the layer position was
     // updated above.
 
     if (m_marquee)
         m_marquee->updateMarqueePosition();
 }
 
 void RenderLayer::updateTransform()
@@ skipping 3865 matching lines @@
     }
 }
 
 void showLayerTree(const WebCore::RenderObject* renderer)
 {
     if (!renderer)
         return;
     showLayerTree(renderer->enclosingLayer());
 }
 #endif