Layers that have a backdrop-filter should paints contents

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

 // Copyright 2014 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/TableSectionPainter.h"
 
 #include "core/layout/LayoutTable.h"
 #include "core/layout/LayoutTableCell.h"
 #include "core/layout/LayoutTableCol.h"
 #include "core/layout/LayoutTableRow.h"
@@ skipping 177 matching lines @@
         LayoutTable::ColAndColGroup colAndColGroup = m_layoutTableSection.table()->colElement(cell.col());
         LayoutTableCol* column = colAndColGroup.col;
         LayoutTableCol* columnGroup = colAndColGroup.colgroup;
         TableCellPainter tableCellPainter(cell);
 
         // Column groups and columns first.
         // FIXME: Columns and column groups do not currently support opacity, and they are being painted "too late" in
         // the stack, since we have already opened a transparency layer (potentially) for the table row group.
         // Note that we deliberately ignore whether or not the cell has a layer, since these backgrounds paint "behind" the
         // cell.
-        if (columnGroup && columnGroup->hasBackground())
+        if (columnGroup && (columnGroup->hasBackground() || columnGroup->styleRef().hasBackdropFilter()))
             tableCellPainter.paintBackgroundsBehindCell(paintInfoForCells, cellPoint, columnGroup, DisplayItem::TableCellBackgroundFromColumnGroup);
-        if (column && column->hasBackground())
+        if (column && (column->hasBackground() || column->styleRef().hasBackdropFilter()))
             tableCellPainter.paintBackgroundsBehindCell(paintInfoForCells, cellPoint, column, DisplayItem::TableCellBackgroundFromColumn);
 
         // Paint the row group next.
-        if (m_layoutTableSection.hasBackground())
+        if (m_layoutTableSection.hasBackground() || m_layoutTableSection.styleRef().hasBackdropFilter())
             tableCellPainter.paintBackgroundsBehindCell(paintInfoForCells, cellPoint, &m_layoutTableSection, DisplayItem::TableCellBackgroundFromSection);
     }
 
     if (shouldPaintDescendantBlockBackgrounds(originalPaintPhase)) {
         // Paint the row next, but only if it doesn't have a layer. If a row has a layer, it will be responsible for
         // painting the row background for the cell.
-        if (row->hasBackground() && !row->hasSelfPaintingLayer())
+        if ((row->hasBackground() || row->styleRef().hasBackdropFilter()) && !row->hasSelfPaintingLayer())

[pdr., 2016/02/03 04:20:28]

Can you add a test for this that fails without the patch and passes with?

             TableCellPainter(cell).paintBackgroundsBehindCell(paintInfoForCells, cellPoint, row, DisplayItem::TableCellBackgroundFromRow);
     }
 
     if (originalPaintPhase != PaintPhaseSelfBlockBackgroundOnly && !cell.hasSelfPaintingLayer() && !row->hasSelfPaintingLayer())
         cell.paint(paintInfoForCells, cellPoint);
 }
 
 } // namespace blink