Implement a Hit Test Cache.

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 1510 matching lines @@
 
     if (hasOverflowingCell()) {
         for (LayoutTableRow* 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 (!row->hasSelfPaintingLayer()) {
                 LayoutPoint childPoint = flipForWritingModeForChild(row, adjustedLocation);
                 if (row->nodeAtPoint(result, locationInContainer, childPoint, action)) {
-                    updateHitTestResult(result, toLayoutPoint(locationInContainer.point() - childPoint));
+                    // TODO(dtapuska): Calculate correct box for row.
+                    updateHitTestResult(result, toLayoutPoint(locationInContainer.point() - childPoint), result.validityRect());
                     return true;
                 }
             }
         }
         return false;
     }
 
     recalcCellsIfNeeded();
 
     LayoutRect hitTestRect = LayoutRect(locationInContainer.boundingBox());
@@ skipping 10 matching lines @@
 
             // If the cell is empty, there's nothing to do
             if (!current.hasCells())
                 continue;
 
             for (unsigned i = current.cells.size() ; i; ) {
                 --i;
                 LayoutTableCell* cell = current.cells[i];
                 LayoutPoint cellPoint = flipForWritingModeForChild(cell, adjustedLocation);
                 if (static_cast<LayoutObject*>(cell)->nodeAtPoint(result, locationInContainer, cellPoint, action)) {
-                    updateHitTestResult(result, locationInContainer.point() - toLayoutSize(cellPoint));
+                    updateHitTestResult(result, locationInContainer.point() - toLayoutSize(cellPoint), overflowClipRect(adjustedLocation));
                     return true;
                 }
             }
             if (!result.hitTestRequest().listBased())
                 break;
         }
         if (!result.hitTestRequest().listBased())
             break;
     }
 
@@ skipping 49 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(table()->columnPositions()[table()->numEffCols()] - table()->columnPositions()[table()->colToEffCol(cell->col() + cell->colSpan())] + horizontalBorderSpacing);
     else
         cellLocation.setX(table()->columnPositions()[effectiveColumn] + horizontalBorderSpacing);
 
     cell->setLogicalLocation(cellLocation);
 }
 
 } // namespace blink