Use tighter typing in table rendering code

Source/core/rendering/RenderTableSection.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 Apple Inc. All rights reserved.
+ * 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
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
@@ skipping 99 matching lines @@
     // Preventively invalidate our cells as we may be re-inserted into
     // a new table which would require us to rebuild our structure.
     setNeedsCellRecalc();
 }
 
 void RenderTableSection::addChild(RenderObject* child, RenderObject* beforeChild)
 {
     if (!child->isTableRow()) {
         RenderObject* last = beforeChild;
         if (!last)
-            last = lastChild();
+            last = lastRow();
         if (last && last->isAnonymous() && !last->isBeforeOrAfterContent()) {
             if (beforeChild == last)
                 beforeChild = last->slowFirstChild();
             last->addChild(child, beforeChild);
             return;
         }
 
         if (beforeChild && !beforeChild->isAnonymous() && beforeChild->parent() == this) {
             RenderObject* row = beforeChild->previousSibling();
             if (row && row->isTableRow() && row->isAnonymous()) {
@@ skipping 939 matching lines @@
         return 0;
 
     unsigned borderWidth = 0;
 
     const BorderValue& sb = side == BorderBefore ? style()->borderBefore() : style()->borderAfter();
     if (sb.style() == BHIDDEN)
         return -1;
     if (sb.style() > BHIDDEN)
         borderWidth = sb.width();
 
-    const BorderValue& rb = side == BorderBefore ? firstChild()->style()->borderBefore() : lastChild()->style()->borderAfter();
+    const BorderValue& rb = side == BorderBefore ? firstRow()->style()->borderBefore() : lastRow()->style()->borderAfter();
     if (rb.style() == BHIDDEN)
         return -1;
     if (rb.style() > BHIDDEN && rb.width() > borderWidth)
         borderWidth = rb.width();
 
     bool allHidden = true;
     for (unsigned c = 0; c < totalCols; c++) {
         const CellStruct& current = cellAt(side == BorderBefore ? 0 : m_grid.size() - 1, c);
         if (current.inColSpan || !current.hasCells())
             continue;
@@ skipping 392 matching lines @@
     ASSERT(m_needsCellRecalc);
     // We reset the flag here to ensure that |addCell| works. This is safe to do as
     // fillRowsWithDefaultStartingAtPosition makes sure we match the table's columns
     // representation.
     m_needsCellRecalc = false;
 
     m_cCol = 0;
     m_cRow = 0;
     m_grid.clear();
 
-    for (RenderObject* row = firstChild(); row; row = row->nextSibling()) {
-        if (row->isTableRow()) {
-            unsigned insertionRow = m_cRow;
-            m_cRow++;
-            m_cCol = 0;
-            ensureRows(m_cRow);
+    for (RenderTableRow* row = firstRow(); row; row = row->nextRow()) {
+        unsigned insertionRow = m_cRow;
+        ++m_cRow;
+        m_cCol = 0;
+        ensureRows(m_cRow);
 
-            RenderTableRow* tableRow = toRenderTableRow(row);
-            m_grid[insertionRow].rowRenderer = tableRow;
-            tableRow->setRowIndex(insertionRow);
-            setRowLogicalHeightToRowStyleLogicalHeight(m_grid[insertionRow]);
+        m_grid[insertionRow].rowRenderer = row;
+        row->setRowIndex(insertionRow);
+        setRowLogicalHeightToRowStyleLogicalHeight(m_grid[insertionRow]);
 
-            for (RenderObject* cell = tableRow->firstChild(); cell; cell = cell->nextSibling()) {
-                if (!cell->isTableCell())
-                    continue;
-
-                RenderTableCell* tableCell = toRenderTableCell(cell);
-                addCell(tableCell, tableRow);
-            }
-        }
+        for (RenderTableCell* cell = row->firstCell(); cell; cell = cell->nextCell())
+            addCell(cell, row);
     }
 
     m_grid.shrinkToFit();
     setNeedsLayout();
 }
 
 // FIXME: This function could be made O(1) in certain cases (like for the non-most-constrainive cells' case).
 void RenderTableSection::rowLogicalHeightChanged(unsigned rowIndex)
 {
     if (needsCellRecalc())
         return;
 
     setRowLogicalHeightToRowStyleLogicalHeight(m_grid[rowIndex]);
 
-    for (RenderObject* cell = m_grid[rowIndex].rowRenderer->firstChild(); cell; cell = cell->nextSibling()) {
-        if (!cell->isTableCell())
-            continue;
-
-        updateLogicalHeightForCell(m_grid[rowIndex], toRenderTableCell(cell));
-    }
+    for (RenderTableCell* cell = m_grid[rowIndex].rowRenderer->firstCell(); cell; cell = cell->nextCell())
+        updateLogicalHeightForCell(m_grid[rowIndex], cell);
 }
 
 void RenderTableSection::setNeedsCellRecalc()
 {
     m_needsCellRecalc = true;
     if (RenderTable* t = table())
         t->setNeedsSectionRecalc();
 }
 
 unsigned RenderTableSection::numColumns() const
@@ skipping 65 matching lines @@
         } else {
             r[pos + 1].inColSpan = 0;
         }
     }
 }
 
 // Hit Testing
 bool RenderTableSection::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction action)
 {
     // If we have no children then we have nothing to do.
-    if (!firstChild())
+    if (!firstRow())
         return false;
 
     // Table sections cannot ever be hit tested.  Effectively they do not exist.
     // Just forward to our children always.
     LayoutPoint adjustedLocation = accumulatedOffset + location();
 
     if (hasOverflowClip() && !locationInContainer.intersects(overflowClipRect(adjustedLocation)))
         return false;
 
     if (hasOverflowingCell()) {
-        for (RenderObject* child = lastChild(); child; child = child->previousSibling()) {
+        for (RenderTableRow* row = lastRow(); row; row = row->previousRow()) {
             // FIXME: We have to skip over inline flows, since they can show up inside table rows
             // at the moment (a demoted inline <form> for example). If we ever implement a
             // table-specific hit-test method (which we should do for performance reasons anyway),
             // then we can remove this check.
-            if (child->isBox() && !toRenderBox(child)->hasSelfPaintingLayer()) {
-                LayoutPoint childPoint = flipForWritingModeForChild(toRenderBox(child), adjustedLocation);
-                if (child->nodeAtPoint(request, result, locationInContainer, childPoint, action)) {
+            if (!row->hasSelfPaintingLayer()) {
+                LayoutPoint childPoint = flipForWritingModeForChild(row, adjustedLocation);
+                if (row->nodeAtPoint(request, result, locationInContainer, childPoint, action)) {
                     updateHitTestResult(result, toLayoutPoint(locationInContainer.point() - childPoint));
                     return true;
                 }
             }
         }
         return false;
     }
 
     recalcCellsIfNeeded();
 
@@ skipping 77 matching lines @@
     else
         cellLocation.setX(table()->columnPositions()[effectiveColumn] + horizontalBorderSpacing);
 
     cell->setLogicalLocation(cellLocation);
 
     if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
         view()->addLayoutDelta(oldCellLocation - cell->location());
 }
 
 } // namespace WebCore