Extract LayoutTableSection::CellStruct to a standalone class TableGridCell

third_party/WebKit/Source/core/layout/LayoutTableSection.h

Index: third_party/WebKit/Source/core/layout/LayoutTableSection.h
diff --git a/third_party/WebKit/Source/core/layout/LayoutTableSection.h b/third_party/WebKit/Source/core/layout/LayoutTableSection.h
index 5701079d7a5c8044fe1309252a6fae08d25b1b0e..7f0ffe2e20ac4bf6de71ce4cf718e0569cfb6319 100644
--- a/third_party/WebKit/Source/core/layout/LayoutTableSection.h
+++ b/third_party/WebKit/Source/core/layout/LayoutTableSection.h
@@ -29,6 +29,7 @@
 #include "core/CoreExport.h"
 #include "core/layout/LayoutTable.h"
 #include "core/layout/LayoutTableBoxComponent.h"
+#include "core/layout/TableGridCell.h"
 #include "platform/wtf/Vector.h"
 
 namespace blink {
@@ -126,61 +127,6 @@ class CORE_EXPORT LayoutTableSection final : public LayoutTableBoxComponent {
 
   typedef Vector<LayoutTableCell*, 2> SpanningLayoutTableCells;
 
-  // CellStruct represents the cells that occupy an (N, M) position in the
-  // table grid.
-  struct CellStruct {
-    DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
-
-   public:
-    // All the cells that fills this grid "slot".
-    // Due to colspan / rowpsan, it is possible to have overlapping cells
-    // (see class comment about an example).
-    // This Vector is sorted in DOM order.
-    Vector<LayoutTableCell*, 1> cells;
-    bool in_col_span;  // true for columns after the first in a colspan
-
-    CellStruct();
-    ~CellStruct();
-
-    // This is the cell in the grid "slot" that is on top of the others
-    // (aka the last cell in DOM order for this slot).
-    //
-    // Multiple grid slots can have the same primary cell if the cell spans
-    // into the grid slots. The slot having the smallest row index and
-    // smallest effective column index is the originating slot of the cell.
-    //
-    // The concept of a primary cell is dubious at most as it doesn't
-    // correspond to a DOM or rendering concept. Also callers should be
-    // careful about assumptions about it. For example, even though the
-    // primary cell is visibly the top most, it is not guaranteed to be
-    // the only one visible for this slot due to different visual
-    // overflow rectangles.
-    LayoutTableCell* PrimaryCell() {
-      return HasCells() ? cells[cells.size() - 1] : 0;
-    }
-
-    const LayoutTableCell* PrimaryCell() const {
-      return HasCells() ? cells[cells.size() - 1] : 0;
-    }
-
-    bool HasCells() const { return cells.size() > 0; }
-  };
-
-  // The index is effective column index.
-  typedef Vector<CellStruct> Row;
-
-  struct RowStruct {
-    DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
-
-   public:
-    RowStruct() : row_layout_object(nullptr), baseline(-1) {}
-
-    Row row;
-    LayoutTableRow* row_layout_object;
-    int baseline;
-    Length logical_height;
-  };
-
   struct SpanningRowsHeight {
     STACK_ALLOCATED();
     WTF_MAKE_NONCOPYABLE(SpanningRowsHeight);
@@ -217,17 +163,18 @@ class CORE_EXPORT LayoutTableSection final : public LayoutTableBoxComponent {
   const LayoutTableCell* FirstRowCellAdjoiningTableStart() const;
   const LayoutTableCell* FirstRowCellAdjoiningTableEnd() const;
 
-  CellStruct& CellAt(unsigned row, unsigned effective_column) {
-    return grid_[row].row[effective_column];
+  TableGridCell& GridCellAt(unsigned row, unsigned effective_column) {
+    return grid_[row].grid_cells[effective_column];
   }
-  const CellStruct& CellAt(unsigned row, unsigned effective_column) const {
-    return grid_[row].row[effective_column];
+  const TableGridCell& GridCellAt(unsigned row,
+                                  unsigned effective_column) const {
+    return grid_[row].grid_cells[effective_column];
   }
   LayoutTableCell* PrimaryCellAt(unsigned row, unsigned effective_column) {
-    Row& row_vector = grid_[row].row;
-    if (effective_column >= row_vector.size())
+    auto& grid_cells = grid_[row].grid_cells;
+    if (effective_column >= grid_cells.size())
       return nullptr;
-    return row_vector[effective_column].PrimaryCell();
+    return grid_cells[effective_column].PrimaryCell();
   }
   const LayoutTableCell* PrimaryCellAt(unsigned row,
                                        unsigned effective_column) const {
@@ -244,15 +191,13 @@ class CORE_EXPORT LayoutTableSection final : public LayoutTableBoxComponent {
         row, effective_column);
   }
 
-  unsigned NumCols(unsigned row) const { return grid_[row].row.size(); }
+  unsigned NumCols(unsigned row) const { return grid_[row].grid_cells.size(); }
 
   // Returns null for cells with a rowspan that exceed the last row. Possibly
   // others.
-  LayoutTableRow* RowLayoutObjectAt(unsigned row) {
-    return grid_[row].row_layout_object;
-  }
+  LayoutTableRow* RowLayoutObjectAt(unsigned row) { return grid_[row].row; }
   const LayoutTableRow* RowLayoutObjectAt(unsigned row) const {
-    return grid_[row].row_layout_object;
+    return grid_[row].row;
   }
 
   void AppendEffectiveColumn(unsigned pos);
@@ -372,7 +317,7 @@ class CORE_EXPORT LayoutTableSection final : public LayoutTableBoxComponent {
   void WillBeRemovedFromTree() override;
 
   int BorderSpacingForRow(unsigned row) const {
-    return grid_[row].row_layout_object ? Table()->VBorderSpacing() : 0;
+    return grid_[row].row ? Table()->VBorderSpacing() : 0;
   }
 
   void EnsureRows(unsigned num_rows) {
@@ -382,7 +327,7 @@ class CORE_EXPORT LayoutTableSection final : public LayoutTableBoxComponent {
 
   void EnsureCols(unsigned row_index, unsigned num_cols) {
     if (num_cols > this->NumCols(row_index))
-      grid_[row_index].row.Grow(num_cols);
+      grid_[row_index].grid_cells.Grow(num_cols);
   }
 
   bool RowHasOnlySpanningCells(unsigned);
@@ -446,8 +391,22 @@ class CORE_EXPORT LayoutTableSection final : public LayoutTableBoxComponent {
 
   bool PaintedOutputOfObjectHasNoEffectRegardlessOfSize() const override;
 
-  // The representation of the rows and their cells (CellStruct).
-  Vector<RowStruct> grid_;
+  struct GridRow {

[dgrogan, 2017/05/15 19:53:38]

TableGridRow for consistency with the new class?

[Xianzhu, 2017/05/15 20:28:38]

Done.

+    DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
+
+   public:
+    inline void SetRowLogicalHeightToRowStyleLogicalHeight();
+    inline void UpdateLogicalHeightForCell(const LayoutTableCell*);
+
+    // The index is effective column index.
+    Vector<TableGridCell> grid_cells;

[dgrogan, 2017/05/15 19:53:38]

This is so much clearer than the old "typedef Vector<blah> row".

+    LayoutTableRow* row = nullptr;

[dgrogan, 2017/05/15 19:53:38]

I know it's longer, but wdyt about s/row/layout_table_row/ or reverting back to
row_layout_object? This CL does a great job disambiguating layout objects from
grid objects except here, where it's not clear from the member name which it is.

Eh, after reading the whole CL, it's not that hard to remember that row means
LayoutTableRow. Up to you.

[Xianzhu, 2017/05/15 20:28:38]

I prefer the shorter name :)

+    int baseline = -1;
+    Length logical_height;
+  };
+
+  // The representation of the rows and their grid cells.
+  Vector<GridRow> grid_;
 
   // The logical offset of each row from the top of the section.
   //