Use appropriate background object visual rect for composited table cell backgrounds.

third_party/WebKit/Source/core/layout/LayoutTableCell.cpp

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc.
  *               All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 28 matching lines @@
 #include "platform/geometry/TransformState.h"
 #include "wtf/PtrUtil.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 struct SameSizeAsLayoutTableCell : public LayoutBlockFlow {
   unsigned bitfields;
   int paddings[2];
-  void* pointer;
+  void* pointer1;
+  void* pointer2;
 };
 
 static_assert(sizeof(LayoutTableCell) == sizeof(SameSizeAsLayoutTableCell),
               "LayoutTableCell should stay small");
 static_assert(sizeof(CollapsedBorderValue) == 8,
               "CollapsedBorderValue should stay small");
 
 LayoutTableCell::LayoutTableCell(Element* element)
     : LayoutBlockFlow(element),
       m_absoluteColumnIndex(unsetColumnIndex),
@@ skipping 396 matching lines @@
   // The baseline of a cell is the baseline of the first in-flow line box in the
   // cell, or the first in-flow table-row in the cell, whichever comes first. If
   // there is no such line box or table-row, the baseline is the bottom of
   // content edge of the cell box.
   int firstLineBaseline = firstLineBoxBaseline();
   if (firstLineBaseline != -1)
     return firstLineBaseline;
   return (borderBefore() + paddingBefore() + contentLogicalHeight()).toInt();
 }
 
+void LayoutTableCell::ensureIsReadyForPaintInvalidation() {
+  if (!m_rowBackgroundDisplayItemClient &&
+      usesCompositedCellDisplayItemClients()) {
+    m_rowBackgroundDisplayItemClient =
+        wrapUnique(new LayoutTableCell::RowBackgroundDisplayItemClient(*row()));
+  }
+  LayoutBlockFlow::ensureIsReadyForPaintInvalidation();
+}
+
 void LayoutTableCell::styleDidChange(StyleDifference diff,
                                      const ComputedStyle* oldStyle) {
   DCHECK_EQ(style()->display(), EDisplay::TableCell);
 
   LayoutBlockFlow::styleDidChange(diff, oldStyle);
   setHasBoxDecorationBackground(true);
 
   if (parent() && section() && oldStyle &&
       style()->height() != oldStyle->height())
     section()->rowLogicalHeightChanged(row());
@@ skipping 939 matching lines @@
 bool LayoutTableCell::backgroundIsKnownToBeOpaqueInRect(
     const LayoutRect& localRect) const {
   // If this object has layer, the area of collapsed borders should be
   // transparent to expose the collapsed borders painted on the underlying
   // layer.
   if (hasLayer() && table()->collapseBorders())
     return false;
   return LayoutBlockFlow::backgroundIsKnownToBeOpaqueInRect(localRect);
 }
 
-bool LayoutTableCell::usesTableAsAdditionalDisplayItemClient() const {
-  // In certain cases such as collapsed borders for composited table cells we
-  // paint content for the cell into the table graphics layer backing and so
-  // must use the table's visual rect.
+LayoutTableCell::RowBackgroundDisplayItemClient::RowBackgroundDisplayItemClient(
+    const LayoutTableRow& layoutTableRow)
+    : m_layoutTableRow(layoutTableRow) {}
+
+String LayoutTableCell::RowBackgroundDisplayItemClient::debugName() const {
+  return "RowBackground";
+}
+
+LayoutRect LayoutTableCell::RowBackgroundDisplayItemClient::visualRect() const {
+  return m_layoutTableRow.visualRect();
+}
+
+bool LayoutTableCell::usesCompositedCellDisplayItemClients() const {

[wkorman, 2016/11/03 01:41:25]

This is a bit of a misnomer since it's also true for SPv2, not just composited
cells, but I couldn't think of something better and I believe we want to use
this same logic for both the table and row case. 'isCompositedOrSPv2' or similar
just seemed unwieldy.

[Xianzhu, 2016/11/03 03:06:48]

I think this is OK. When we remove non-SPv2 code, we'll remove this function and
always use rowBackgroundDisplayItemClient.

+  // Table cells are painted in two special ways that require the use of custom
+  // display item clients when the cell is composited:
+  //
+  // 1. When painting row background we paint content for the cell into the
+  // table row graphics layer backing and so must use the row's visual rect.
+  //
+  // 2. When painting collapsed borders we paint content for the cell into the
+  // table graphics layer backing and so must use the table's visual rect.
   return (hasLayer() && layer()->compositingState() != NotComposited) ||
          RuntimeEnabledFeatures::slimmingPaintV2Enabled();
 }
 
 void LayoutTableCell::invalidateDisplayItemClients(
     PaintInvalidationReason reason) const {
-  if (m_collapsedBorderValues && usesTableAsAdditionalDisplayItemClient()) {
-    ObjectPaintInvalidator(*this).invalidateDisplayItemClient(
-        *m_collapsedBorderValues, reason);
+  if (usesCompositedCellDisplayItemClients()) {
+    ObjectPaintInvalidator invalidator(*this);
+    DCHECK(m_rowBackgroundDisplayItemClient);
+    if (m_collapsedBorderValues) {
+      invalidator.invalidateDisplayItemClient(*m_collapsedBorderValues, reason);
+    }
+    invalidator.invalidateDisplayItemClient(*m_rowBackgroundDisplayItemClient,

[wkorman, 2016/11/03 01:41:25]

This wasn't necessary for all tests to pass but I believe we need to do this to
be correct, unless it's sufficient for us to rely on the one explicit
invalidation of this display item client in TablePaintInvalidator?

+                                            reason);
   }
   LayoutBlockFlow::invalidateDisplayItemClients(reason);
 }
 
 // TODO(lunalu): Deliberately dump the "inner" box of table cells, since that
 // is what current results reflect.  We'd like to clean up the results to dump
 // both the outer box and the intrinsic padding so that both bits of information
 // are captured by the results.
 LayoutRect LayoutTableCell::debugRect() const {
   LayoutRect rect = LayoutRect(
       location().x(), location().y() + intrinsicPaddingBefore(), size().width(),
       size().height() - intrinsicPaddingBefore() - intrinsicPaddingAfter());
 
   LayoutBlock* cb = containingBlock();
   if (cb)
     cb->adjustChildDebugRect(rect);
 
   return rect;
 }
 
 void LayoutTableCell::adjustChildDebugRect(LayoutRect& r) const {
   r.move(0, -intrinsicPaddingBefore());
 }
 
 }  // namespace blink