Paint collapsed borders of a table as one display item

third_party/WebKit/Source/core/paint/PaintInvalidator.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/paint/PaintInvalidator.h"
 
 #include "core/editing/FrameSelection.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
@@ skipping 191 matching lines @@
   if (object.styleRef().hasOutline())
     context.paintingLayer->setNeedsPaintPhaseDescendantOutlines();
 
   if (object.hasBoxDecorationBackground()
       // We also paint overflow controls in background phase.
       || (object.hasOverflowClip() &&
           toLayoutBox(object).getScrollableArea()->hasOverflowControls())) {
     context.paintingLayer->setNeedsPaintPhaseDescendantBlockBackgrounds();
   }
 
-  if (object.isTable()) {
-    const LayoutTable& table = toLayoutTable(object);
-    if (table.collapseBorders() && !table.collapsedBorders().isEmpty())
-      context.paintingLayer->setNeedsPaintPhaseDescendantBlockBackgrounds();
-  }
+  if (object.isTable() && toLayoutTable(object).hasCollapsedBorders())

[chrishtr, 2016/11/03 21:16:29]

The old code was just inaccurate I guess?

[Xianzhu, 2016/11/03 21:26:55]

They are equivalent. The new function LayoutTable::hasCollapsedBorders() checks
the same condition.

+    context.paintingLayer->setNeedsPaintPhaseDescendantBlockBackgrounds();
 }
 
 namespace {
 
 // This is temporary to workaround paint invalidation issues in
 // non-rootLayerScrolls mode.
 // It undoes FrameView's content clip and scroll for paint invalidation of frame
 // scroll controls and the LayoutView to which the content clip and scroll don't
 // apply.
 class ScopedUndoFrameViewContentClipAndScroll {
@@ skipping 224 matching lines @@
   object.getMutableForPainting().clearPaintInvalidationFlags();
 }
 
 void PaintInvalidator::processPendingDelayedPaintInvalidations() {
   for (auto target : m_pendingDelayedPaintInvalidations)
     target->getMutableForPainting().setShouldDoFullPaintInvalidation(
         PaintInvalidationDelayedFull);
 }
 
 }  // namespace blink