Handle nested theads correctly when paginated

third_party/WebKit/Source/core/layout/LayoutTableSection.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, 2008, 2009, 2010, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 89 matching lines @@
     : LayoutTableBoxComponent(element)
     , m_cCol(0)
     , m_cRow(0)
     , m_outerBorderStart(0)
     , m_outerBorderEnd(0)
     , m_outerBorderBefore(0)
     , m_outerBorderAfter(0)
     , m_needsCellRecalc(false)
     , m_forceSlowPaintPathWithOverflowingCell(false)
     , m_hasMultipleCellLevels(false)
+    , m_offsetForRepeatingHeader(LayoutUnit())
 {
     // init LayoutObject attributes
     setInline(false); // our object is not Inline
 }
 
 LayoutTableSection::~LayoutTableSection()
 {
 }
 
 void LayoutTableSection::styleDidChange(StyleDifference diff, const ComputedStyle* oldStyle)
@@ skipping 840 matching lines @@
 
     unsigned totalRows = m_grid.size();
 
     // Set the width of our section now.  The rows will also be this width.
     setLogicalWidth(table()->contentLogicalWidth());
 
     int vspacing = table()->vBorderSpacing();
     unsigned nEffCols = table()->numEffectiveColumns();
     bool isPaginated = view()->layoutState()->isPaginated();
 
+    if (isPaginated) {
+        LayoutTableSection* header = table()->header();
+        // If we're a table header nested inside a table cell then we want to repeat on each
+        // page, but below the header we're nested inside. Note we don't try to match the padding
+        // on the cell on each repeated header.
+        if (header && header == this)
+            setOffsetForRepeatingHeader(view()->layoutState()->heightOffsetForTableHeaders());
+    }
+
     LayoutState state(*this, locationOffset());
 
     for (unsigned r = 0; r < totalRows; r++) {
         // Set the row's x/y position and width/height.
         LayoutTableRow* rowLayoutObject = m_grid[r].rowLayoutObject;
         int paginationStrutOnRow = 0;
         if (rowLayoutObject) {
             rowLayoutObject->setLocation(LayoutPoint(0, m_rowPos[r]));
             rowLayoutObject->setLogicalWidth(logicalWidth());
             rowLayoutObject->setLogicalHeight(LayoutUnit(m_rowPos[r + 1] - m_rowPos[r] - vspacing));
             rowLayoutObject->updateLayerTransformAfterLayout();
             if (isPaginated) {
                 paginationStrutOnRow = paginationStrutForRow(rowLayoutObject, LayoutUnit(m_rowPos[r]));
                 if (paginationStrutOnRow) {
-                    LayoutTableSection* header = table()->header();
                     // If we have a header group we will paint it at the top of each page, move the rows
                     // down to accomodate it.
-                    if (header && header != this)
-                        paginationStrutOnRow += header->logicalHeight().toInt();
+                    paginationStrutOnRow += state.heightOffsetForTableHeaders().toInt();
                     for (unsigned rowIndex = r; rowIndex <= totalRows; rowIndex++)
                         m_rowPos[rowIndex] += paginationStrutOnRow;
                 }
             }
         }
 
         int rowHeightIncreaseForPagination = INT_MIN;
 
         for (unsigned c = 0; c < nEffCols; c++) {
             CellStruct& cs = cellAt(r, c);
@@ skipping 677 matching lines @@
     // FIXME: The table's direction should determine our row's direction, not the section's (see bug 96691).
     if (!style()->isLeftToRightDirection())
         cellLocation.setX(LayoutUnit(table()->effectiveColumnPositions()[table()->numEffectiveColumns()] - table()->effectiveColumnPositions()[table()->absoluteColumnToEffectiveColumn(cell->absoluteColumnIndex() + cell->colSpan())] + horizontalBorderSpacing));
     else
         cellLocation.setX(LayoutUnit(table()->effectiveColumnPositions()[effectiveColumn] + horizontalBorderSpacing));
 
     cell->setLogicalLocation(cellLocation);
 }
 
 } // namespace blink