Improve LayoutTable outer collapsed border calculation

Remove code in LayoutTable and LayoutTableSection for computing outer
borders. Use cells' cached collapsed borders instead.

This is mostly a pure refactoring, except it affects some corner cases:
- Previously collapsed borders for colgroup were not included in table's
  border. See changes to results of
  paint/invalidation/table/cached-change-border-color.html.
- Previously when the row and the table were in different inline
  direction and the the width of some collapsed border was in odd
  number, the distribution of the 1 pixel into half outer and inner
  borders was inconsistent. Now we always give the 1 pixel in the
  same way defined in LayoutTableCell::CollapsedBOrderHalfXXX().
  See changes to results of fast/table/border-collapsing/002.html.

Change-Id: I74e6d9173e5d46933fa7456cb713c370e9e7d464
Reviewed-on: https://chromium-review.googlesource.com/515606
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: David Grogan <dgrogan@chromium.org>
Reviewed-by: Walter Korman <wkorman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#476219}

third_party/WebKit/LayoutTests/paint/invalidation/table/cached-change-colgroup-border-color-expected.txt

@@ -8,7 +8,7 @@
       "paintInvalidations": [
         {
           "object": "LayoutTableCol COLGROUP id='colgroup'",
-          "rect": [8, 8, 166, 102],
+          "rect": [8, 8, 167, 104],
           "reason": "style change"
         }
       ]

third_party/WebKit/LayoutTests/paint/invalidation/table/cached-change-colgroup-border-width-expected.txt

@@ -6,44 +6,54 @@
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
+        {
+          "object": "LayoutTableCol COLGROUP id='colgroup'",
+          "rect": [8, 8, 167, 104],
+          "reason": "style change"
+        },
         {
           "object": "LayoutTableSection TBODY",
-          "rect": [7, 7, 167, 104],
+          "rect": [8, 8, 167, 104],
           "reason": "geometry"
         },
         {
-          "object": "LayoutTableCol COLGROUP id='colgroup'",
-          "rect": [8, 8, 166, 102],
-          "reason": "style change"
+          "object": "LayoutTable TABLE",
+          "rect": [8, 108, 167, 4],
+          "reason": "incremental"
+        },
+        {
+          "object": "LayoutTableCell TD",
+          "rect": [64, 8, 58, 53],
+          "reason": "geometry"
         },
         {
           "object": "LayoutTableCell TD",
-          "rect": [63, 7, 58, 53],
+          "rect": [8, 59, 58, 53],
           "reason": "geometry"
         },
         {
           "object": "LayoutTableCell TD",
-          "rect": [7, 58, 58, 53],
+          "rect": [8, 8, 58, 53],
           "reason": "geometry"
         },
         {
           "object": "LayoutTableCell TD",
-          "rect": [7, 7, 58, 53],
+          "rect": [118, 60, 57, 52],
           "reason": "geometry"
         },
         {
           "object": "LayoutTableCell TD",
-          "rect": [117, 59, 57, 52],
+          "rect": [118, 8, 57, 52],
           "reason": "geometry"
         },
         {
           "object": "LayoutTableCell TD",
-          "rect": [117, 7, 57, 52],
+          "rect": [65, 60, 57, 52],
           "reason": "geometry"
         },
         {
           "object": "LayoutTableCell TD",
-          "rect": [64, 59, 57, 52],
+          "rect": [8, 58, 56, 52],
           "reason": "geometry"
         },
         {
@@ -68,7 +78,7 @@
         },
         {
           "object": "LayoutTable TABLE",
-          "rect": [169, 8, 5, 102],
+          "rect": [169, 8, 6, 104],
           "reason": "incremental"
         }
       ]
@@ -111,6 +121,10 @@
       "object": "LayoutTableSection TBODY",
       "reason": "geometry"
     },
+    {
+      "object": "LayoutTableRow TR",
+      "reason": "geometry"
+    },
     {
       "object": "LayoutTableCell TD",
       "reason": "geometry"
@@ -123,6 +137,10 @@
       "object": "LayoutTableCell TD",
       "reason": "geometry"
     },
+    {
+      "object": "LayoutTableRow TR",
+      "reason": "geometry"
+    },
     {
       "object": "LayoutTableCell TD",
       "reason": "geometry"

third_party/WebKit/LayoutTests/platform/mac-mac10.10/fast/forms/file/file-input-direction-expected.txt

-layer at (0,0) size 800x600 scrollWidth 970
+layer at (0,0) size 800x600 scrollWidth 971
   LayoutView at (0,0) size 800x600
 layer at (0,0) size 800x600
   LayoutBlockFlow {HTML} at (0,0) size 800x600

third_party/WebKit/LayoutTests/platform/mac-mac10.9/fast/forms/file/file-input-direction-expected.txt

-layer at (0,0) size 800x600 scrollWidth 1070
+layer at (0,0) size 800x600 scrollWidth 1071
   LayoutView at (0,0) size 800x600
 layer at (0,0) size 800x600
   LayoutBlockFlow {HTML} at (0,0) size 800x600

third_party/WebKit/LayoutTests/platform/mac/fast/forms/file/file-input-direction-expected.txt

-layer at (0,0) size 800x600 scrollWidth 1066
+layer at (0,0) size 800x600 scrollWidth 1067
   LayoutView at (0,0) size 800x600
 layer at (0,0) size 800x600
   LayoutBlockFlow {HTML} at (0,0) size 800x600

third_party/WebKit/Source/core/BUILD.gn

@@ -1315,6 +1315,7 @@ source_set("unit_tests") {
     "layout/LayoutTableCellTest.cpp",
     "layout/LayoutTableRowTest.cpp",
     "layout/LayoutTableSectionTest.cpp",
+    "layout/LayoutTableTest.cpp",
     "layout/LayoutTestHelper.cpp",
     "layout/LayoutTestHelper.h",
     "layout/LayoutTextTest.cpp",

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

@@ -149,8 +149,8 @@ class CORE_EXPORT LayoutTable final : public LayoutBlock {
     return Style()->BorderCollapse() == EBorderCollapse::kCollapse;
   }
 
-  LayoutUnit BorderStart() const override { return LayoutUnit(border_start_); }
-  LayoutUnit BorderEnd() const override { return LayoutUnit(border_end_); }
+  LayoutUnit BorderStart() const override;
+  LayoutUnit BorderEnd() const override;
   LayoutUnit BorderBefore() const override;
   LayoutUnit BorderAfter() const override;
 
@@ -182,47 +182,6 @@ class CORE_EXPORT LayoutTable final : public LayoutBlock {
     return Style()->IsLeftToRightDirection() ? BorderEnd() : BorderStart();
   }
 
-  int OuterBorderBefore() const;
-  int OuterBorderAfter() const;
-  int OuterBorderStart() const;
-  int OuterBorderEnd() const;
-
-  int OuterBorderLeft() const {
-    if (Style()->IsHorizontalWritingMode())
-      return Style()->IsLeftToRightDirection() ? OuterBorderStart()
-                                               : OuterBorderEnd();
-    return Style()->IsFlippedBlocksWritingMode() ? OuterBorderAfter()
-                                                 : OuterBorderBefore();
-  }
-
-  int OuterBorderRight() const {
-    if (Style()->IsHorizontalWritingMode())
-      return Style()->IsLeftToRightDirection() ? OuterBorderEnd()
-                                               : OuterBorderStart();
-    return Style()->IsFlippedBlocksWritingMode() ? OuterBorderBefore()
-                                                 : OuterBorderAfter();
-  }
-
-  int OuterBorderTop() const {
-    if (Style()->IsHorizontalWritingMode())
-      return Style()->IsFlippedBlocksWritingMode() ? OuterBorderAfter()
-                                                   : OuterBorderBefore();
-    return Style()->IsLeftToRightDirection() ? OuterBorderStart()
-                                             : OuterBorderEnd();
-  }
-
-  int OuterBorderBottom() const {
-    if (Style()->IsHorizontalWritingMode())
-      return Style()->IsFlippedBlocksWritingMode() ? OuterBorderBefore()
-                                                   : OuterBorderAfter();
-    return Style()->IsLeftToRightDirection() ? OuterBorderEnd()
-                                             : OuterBorderStart();
-  }
-
-  int CalcBorderStart() const;
-  int CalcBorderEnd() const;
-  void RecalcBordersInRowDirection();
-
   void AddChild(LayoutObject* child,
                 LayoutObject* before_child = nullptr) override;
 
@@ -274,12 +233,13 @@ class CORE_EXPORT LayoutTable final : public LayoutBlock {
     return row_offset_from_repeating_header_;
   }
 
-  // This function returns 0 if the table has no section.
+  // These functions return nullptr if the table has no sections.
   LayoutTableSection* TopSection() const;
   LayoutTableSection* BottomSection() const;
 
-  // This function returns 0 if the table has no non-empty sections.
+  // These functions return nullptr if the table has no non-empty sections.
   LayoutTableSection* TopNonEmptySection() const;
+  LayoutTableSection* BottomNonEmptySection() const;
 
   unsigned LastEffectiveColumnIndex() const {
     return NumEffectiveColumns() - 1;
@@ -522,6 +482,13 @@ class CORE_EXPORT LayoutTable final : public LayoutBlock {
   void AddOverflowFromChildren() override;
 
   void RecalcSections() const;
+
+  void UpdateCollapsedOuterBorders() const;
+  unsigned ComputeCollapsedOuterBorderBefore() const;
+  unsigned ComputeCollapsedOuterBorderAfter() const;
+  unsigned ComputeCollapsedOuterBorderStart() const;
+  unsigned ComputeCollapsedOuterBorderEnd() const;
+
   void LayoutCaption(LayoutTableCaption&, SubtreeLayoutScope&);
   void LayoutSection(LayoutTableSection&,
                      SubtreeLayoutScope&,
@@ -589,6 +556,7 @@ class CORE_EXPORT LayoutTable final : public LayoutBlock {
   CollapsedBorderValues collapsed_borders_;
   bool collapsed_borders_valid_ : 1;
   bool needs_invalidate_collapsed_borders_for_all_cells_ : 1;
+  mutable bool collapsed_outer_borders_valid_ : 1;
 
   mutable bool has_col_elements_ : 1;
   mutable bool needs_section_recalc_ : 1;
@@ -606,8 +574,11 @@ class CORE_EXPORT LayoutTable final : public LayoutBlock {
 
   short h_spacing_;
   short v_spacing_;
-  int border_start_;
-  int border_end_;
+
+  mutable unsigned collapsed_outer_border_start_;
+  mutable unsigned collapsed_outer_border_end_;
+  mutable unsigned collapsed_outer_border_before_;
+  mutable unsigned collapsed_outer_border_after_;
 
   LayoutUnit block_offset_to_first_repeatable_header_;
   LayoutUnit row_offset_from_repeating_header_;

third_party/WebKit/Source/core/layout/LayoutTableCell.cpp

@@ -433,10 +433,10 @@ void LayoutTableCell::ComputeOverflow(LayoutUnit old_client_after_edge,
   // Our border rect already includes the inner halves of the collapsed borders,
   // so here we get the outer halves.
   bool rtl = !StyleForCellFlow().IsLeftToRightDirection();
-  LayoutUnit left = CollapsedBorderHalfLeft(true);
-  LayoutUnit right = CollapsedBorderHalfRight(true);
-  LayoutUnit top = CollapsedBorderHalfTop(true);
-  LayoutUnit bottom = CollapsedBorderHalfBottom(true);
+  unsigned left = CollapsedBorderHalfLeft(true);
+  unsigned right = CollapsedBorderHalfRight(true);
+  unsigned top = CollapsedBorderHalfTop(true);
+  unsigned bottom = CollapsedBorderHalfBottom(true);
 
   // This cell's borders may be lengthened to match the widths of orthogonal
   // borders of adjacent cells. Expand visual overflow to cover the lengthened
@@ -467,7 +467,8 @@ void LayoutTableCell::ComputeOverflow(LayoutUnit old_client_after_edge,
   }
 
   LayoutRect rect = BorderBoxRect();
-  rect.ExpandEdges(top, right, bottom, left);
+  rect.ExpandEdges(LayoutUnit(top), LayoutUnit(right), LayoutUnit(bottom),
+                   LayoutUnit(left));
   collapsed_border_values_->SetLocalVisualRect(rect);
 }
 
@@ -1136,49 +1137,57 @@ CollapsedBorderValue LayoutTableCell::ComputeCollapsedAfterBorder() const {
 }
 
 LayoutUnit LayoutTableCell::BorderLeft() const {
-  return Table()->ShouldCollapseBorders() ? CollapsedBorderHalfLeft(false)
-                                          : LayoutBlockFlow::BorderLeft();
+  return Table()->ShouldCollapseBorders()
+             ? LayoutUnit(CollapsedBorderHalfLeft(false))
+             : LayoutBlockFlow::BorderLeft();
 }
 
 LayoutUnit LayoutTableCell::BorderRight() const {
-  return Table()->ShouldCollapseBorders() ? CollapsedBorderHalfRight(false)
-                                          : LayoutBlockFlow::BorderRight();
+  return Table()->ShouldCollapseBorders()
+             ? LayoutUnit(CollapsedBorderHalfRight(false))
+             : LayoutBlockFlow::BorderRight();
 }
 
 LayoutUnit LayoutTableCell::BorderTop() const {
-  return Table()->ShouldCollapseBorders() ? CollapsedBorderHalfTop(false)
-                                          : LayoutBlockFlow::BorderTop();
+  return Table()->ShouldCollapseBorders()
+             ? LayoutUnit(CollapsedBorderHalfTop(false))
+             : LayoutBlockFlow::BorderTop();
 }
 
 LayoutUnit LayoutTableCell::BorderBottom() const {
-  return Table()->ShouldCollapseBorders() ? CollapsedBorderHalfBottom(false)
-                                          : LayoutBlockFlow::BorderBottom();
+  return Table()->ShouldCollapseBorders()
+             ? LayoutUnit(CollapsedBorderHalfBottom(false))
+             : LayoutBlockFlow::BorderBottom();
 }
 
 // FIXME: https://bugs.webkit.org/show_bug.cgi?id=46191, make the collapsed
 // border drawing work with different block flow values instead of being
 // hard-coded to top-to-bottom.
 LayoutUnit LayoutTableCell::BorderStart() const {
-  return Table()->ShouldCollapseBorders() ? CollapsedBorderHalfStart(false)
-                                          : LayoutBlockFlow::BorderStart();
+  return Table()->ShouldCollapseBorders()
+             ? LayoutUnit(CollapsedBorderHalfStart(false))
+             : LayoutBlockFlow::BorderStart();
 }
 
 LayoutUnit LayoutTableCell::BorderEnd() const {
-  return Table()->ShouldCollapseBorders() ? CollapsedBorderHalfEnd(false)
-                                          : LayoutBlockFlow::BorderEnd();
+  return Table()->ShouldCollapseBorders()
+             ? LayoutUnit(CollapsedBorderHalfEnd(false))
+             : LayoutBlockFlow::BorderEnd();
 }
 
 LayoutUnit LayoutTableCell::BorderBefore() const {
-  return Table()->ShouldCollapseBorders() ? CollapsedBorderHalfBefore(false)
-                                          : LayoutBlockFlow::BorderBefore();
+  return Table()->ShouldCollapseBorders()
+             ? LayoutUnit(CollapsedBorderHalfBefore(false))
+             : LayoutBlockFlow::BorderBefore();
 }
 
 LayoutUnit LayoutTableCell::BorderAfter() const {
-  return Table()->ShouldCollapseBorders() ? CollapsedBorderHalfAfter(false)
-                                          : LayoutBlockFlow::BorderAfter();
+  return Table()->ShouldCollapseBorders()
+             ? LayoutUnit(CollapsedBorderHalfAfter(false))
+             : LayoutBlockFlow::BorderAfter();
 }
 
-LayoutUnit LayoutTableCell::CollapsedBorderHalfLeft(bool outer) const {
+unsigned LayoutTableCell::CollapsedBorderHalfLeft(bool outer) const {
   const ComputedStyle& style_for_cell_flow = this->StyleForCellFlow();
   if (style_for_cell_flow.IsHorizontalWritingMode()) {
     return style_for_cell_flow.IsLeftToRightDirection()
@@ -1190,7 +1199,7 @@ LayoutUnit LayoutTableCell::CollapsedBorderHalfLeft(bool outer) const {
              : CollapsedBorderHalfBefore(outer);
 }
 
-LayoutUnit LayoutTableCell::CollapsedBorderHalfRight(bool outer) const {
+unsigned LayoutTableCell::CollapsedBorderHalfRight(bool outer) const {
   const ComputedStyle& style_for_cell_flow = this->StyleForCellFlow();
   if (style_for_cell_flow.IsHorizontalWritingMode()) {
     return style_for_cell_flow.IsLeftToRightDirection()
@@ -1202,7 +1211,7 @@ LayoutUnit LayoutTableCell::CollapsedBorderHalfRight(bool outer) const {
              : CollapsedBorderHalfAfter(outer);
 }
 
-LayoutUnit LayoutTableCell::CollapsedBorderHalfTop(bool outer) const {
+unsigned LayoutTableCell::CollapsedBorderHalfTop(bool outer) const {
   const ComputedStyle& style_for_cell_flow = this->StyleForCellFlow();
   if (style_for_cell_flow.IsHorizontalWritingMode()) {
     return style_for_cell_flow.IsFlippedBlocksWritingMode()
@@ -1214,7 +1223,7 @@ LayoutUnit LayoutTableCell::CollapsedBorderHalfTop(bool outer) const {
              : CollapsedBorderHalfEnd(outer);
 }
 
-LayoutUnit LayoutTableCell::CollapsedBorderHalfBottom(bool outer) const {
+unsigned LayoutTableCell::CollapsedBorderHalfBottom(bool outer) const {
   const ComputedStyle& style_for_cell_flow = this->StyleForCellFlow();
   if (style_for_cell_flow.IsHorizontalWritingMode()) {
     return style_for_cell_flow.IsFlippedBlocksWritingMode()
@@ -1226,68 +1235,66 @@ LayoutUnit LayoutTableCell::CollapsedBorderHalfBottom(bool outer) const {
              : CollapsedBorderHalfStart(outer);
 }
 
-LayoutUnit LayoutTableCell::CollapsedBorderHalfStart(bool outer) const {
+unsigned LayoutTableCell::CollapsedBorderHalfStart(bool outer) const {
   UpdateCollapsedBorderValues();
   const auto* collapsed_border_values = this->GetCollapsedBorderValues();
   if (!collapsed_border_values)
-    return LayoutUnit();
+    return 0;
 
   const auto& border = collapsed_border_values->StartBorder();
   if (border.Exists()) {
-    return LayoutUnit(
-        (border.Width() +
-         ((StyleForCellFlow().IsLeftToRightDirection() ^ outer) ? 1 : 0)) /
-        2);  // Give the extra pixel to top and left.
+    return (border.Width() +
+            ((StyleForCellFlow().IsLeftToRightDirection() ^ outer) ? 1 : 0)) /
+           2;  // Give the extra pixel to top and left.
   }
-  return LayoutUnit();
+  return 0;
 }
 
-LayoutUnit LayoutTableCell::CollapsedBorderHalfEnd(bool outer) const {
+unsigned LayoutTableCell::CollapsedBorderHalfEnd(bool outer) const {
   UpdateCollapsedBorderValues();
   const auto* collapsed_border_values = this->GetCollapsedBorderValues();
   if (!collapsed_border_values)
-    return LayoutUnit();
+    return 0;
 
   const auto& border = collapsed_border_values->EndBorder();
   if (border.Exists()) {
-    return LayoutUnit(
-        (border.Width() +
-         ((StyleForCellFlow().IsLeftToRightDirection() ^ outer) ? 0 : 1)) /
-        2);
+    return (border.Width() +
+            ((StyleForCellFlow().IsLeftToRightDirection() ^ outer) ? 0 : 1)) /
+           2;
   }
-  return LayoutUnit();
+  return 0;
 }
 
-LayoutUnit LayoutTableCell::CollapsedBorderHalfBefore(bool outer) const {
+unsigned LayoutTableCell::CollapsedBorderHalfBefore(bool outer) const {
   UpdateCollapsedBorderValues();
   const auto* collapsed_border_values = this->GetCollapsedBorderValues();
   if (!collapsed_border_values)
-    return LayoutUnit();
+    return 0;
 
   const auto& border = collapsed_border_values->BeforeBorder();
   if (border.Exists()) {
-    return LayoutUnit(
-        (border.Width() +
-         ((StyleForCellFlow().IsFlippedBlocksWritingMode() ^ outer) ? 0 : 1)) /
-        2);  // Give the extra pixel to top and left.
+    return (border.Width() +
+            ((StyleForCellFlow().IsFlippedBlocksWritingMode() ^ outer) ? 0
+                                                                       : 1)) /
+           2;  // Give the extra pixel to top and left.
   }
-  return LayoutUnit();
+  return 0;
 }
 
-LayoutUnit LayoutTableCell::CollapsedBorderHalfAfter(bool outer) const {
+unsigned LayoutTableCell::CollapsedBorderHalfAfter(bool outer) const {
   UpdateCollapsedBorderValues();
   const auto* collapsed_border_values = this->GetCollapsedBorderValues();
   if (!collapsed_border_values)
-    return LayoutUnit();
+    return 0;
 
   const auto& border = collapsed_border_values->AfterBorder();
   if (border.Exists()) {
-    return LayoutUnit(
-        (border.Width() +
-         ((StyleForCellFlow().IsFlippedBlocksWritingMode() ^ outer) ? 1 : 0)) /
-        2);
+    return (border.Width() +
+            ((StyleForCellFlow().IsFlippedBlocksWritingMode() ^ outer) ? 1
+                                                                       : 0)) /
+           2;
   }
-  return LayoutUnit();
+  return 0;
 }
 
 void LayoutTableCell::Paint(const PaintInfo& paint_info,

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

@@ -355,6 +355,20 @@ class CORE_EXPORT LayoutTableCell final : public LayoutBlockFlow {
     return cell1->RowIndex() < cell2->RowIndex();
   }
 
+  // For LayoutTable to compute its collapsed outer borders.
+  unsigned CollapsedOuterBorderBefore() const {
+    return CollapsedBorderHalfBefore(true);
+  }
+  unsigned CollapsedOuterBorderAfter() const {
+    return CollapsedBorderHalfAfter(true);
+  }
+  unsigned CollapsedOuterBorderStart() const {
+    return CollapsedBorderHalfStart(true);
+  }
+  unsigned CollapsedOuterBorderEnd() const {
+    return CollapsedBorderHalfEnd(true);
+  }
+
  protected:
   void StyleDidChange(StyleDifference, const ComputedStyle* old_style) override;
   void ComputePreferredLogicalWidths() override;
@@ -388,15 +402,15 @@ class CORE_EXPORT LayoutTableCell final : public LayoutBlockFlow {
                        bool recompute_floats = false) override;
   LayoutRect LocalVisualRect() const override;
 
-  LayoutUnit CollapsedBorderHalfLeft(bool outer) const;
-  LayoutUnit CollapsedBorderHalfRight(bool outer) const;
-  LayoutUnit CollapsedBorderHalfTop(bool outer) const;
-  LayoutUnit CollapsedBorderHalfBottom(bool outer) const;
+  unsigned CollapsedBorderHalfLeft(bool outer) const;
+  unsigned CollapsedBorderHalfRight(bool outer) const;
+  unsigned CollapsedBorderHalfTop(bool outer) const;
+  unsigned CollapsedBorderHalfBottom(bool outer) const;
 
-  LayoutUnit CollapsedBorderHalfStart(bool outer) const;
-  LayoutUnit CollapsedBorderHalfEnd(bool outer) const;
-  LayoutUnit CollapsedBorderHalfBefore(bool outer) const;
-  LayoutUnit CollapsedBorderHalfAfter(bool outer) const;
+  unsigned CollapsedBorderHalfStart(bool outer) const;
+  unsigned CollapsedBorderHalfEnd(bool outer) const;
+  unsigned CollapsedBorderHalfBefore(bool outer) const;
+  unsigned CollapsedBorderHalfAfter(bool outer) const;
 
   void SetIntrinsicPaddingBefore(int p) { intrinsic_padding_before_ = p; }
   void SetIntrinsicPaddingAfter(int p) { intrinsic_padding_after_ = p; }

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

@@ -90,10 +90,6 @@ LayoutTableSection::LayoutTableSection(Element* element)
     : LayoutTableBoxComponent(element),
       c_col_(0),
       c_row_(0),
-      outer_border_start_(0),
-      outer_border_end_(0),
-      outer_border_before_(0),
-      outer_border_after_(0),
       needs_cell_recalc_(false),
       force_full_paint_(false),
       has_multiple_cell_levels_(false),
@@ -1354,174 +1350,6 @@ void LayoutTableSection::MarkAllCellsWidthsDirtyAndOrNeedsLayout(
   }
 }
 
-int LayoutTableSection::CalcBlockDirectionOuterBorder(
-    BlockBorderSide side) const {
-  if (!grid_.size() || !Table()->NumEffectiveColumns())
-    return 0;
-
-  int border_width = 0;
-
-  EBorderStyle section_border_style = side == kBorderBefore
-                                          ? Style()->BorderBeforeStyle()
-                                          : Style()->BorderAfterStyle();
-  if (section_border_style == EBorderStyle::kHidden)
-    return -1;
-  if (ComputedStyle::BorderStyleIsVisible(section_border_style)) {
-    border_width = side == kBorderBefore ? Style()->BorderBeforeWidth()
-                                         : Style()->BorderAfterWidth();
-  }
-
-  EBorderStyle row_border_style = side == kBorderBefore
-                                      ? FirstRow()->Style()->BorderBeforeStyle()
-                                      : LastRow()->Style()->BorderAfterStyle();
-  float row_border_width = side == kBorderBefore
-                               ? FirstRow()->Style()->BorderBeforeWidth()
-                               : LastRow()->Style()->BorderAfterWidth();
-  if (row_border_style == EBorderStyle::kHidden)
-    return -1;
-  if (ComputedStyle::BorderStyleIsVisible(row_border_style) &&
-      row_border_width > border_width)
-    border_width = row_border_width;
-  bool all_hidden = true;
-  unsigned r = side == kBorderBefore ? 0 : grid_.size() - 1;
-  unsigned n_cols = NumCols(r);
-  for (unsigned c = 0; c < n_cols; c++) {
-    const auto& grid_cell = GridCellAt(r, c);
-    if (grid_cell.InColSpan() || !grid_cell.HasCells())
-      continue;
-    const ComputedStyle& primary_cell_style =
-        grid_cell.PrimaryCell()->StyleRef();
-    // FIXME: Make this work with perpendicular and flipped cells.
-    EBorderStyle cell_border_style =
-        side == kBorderBefore ? primary_cell_style.BorderBeforeStyle()
-                              : primary_cell_style.BorderAfterStyle();
-    float cell_border_width = side == kBorderBefore
-                                  ? primary_cell_style.BorderBeforeWidth()
-                                  : primary_cell_style.BorderAfterWidth();
-    // FIXME: Don't repeat for the same col group
-    LayoutTableCol* col =
-        Table()->ColElementAtAbsoluteColumn(c).InnermostColOrColGroup();
-    if (col) {
-      EBorderStyle col_border_style = side == kBorderBefore
-                                          ? col->Style()->BorderBeforeStyle()
-                                          : col->Style()->BorderAfterStyle();
-      const float col_border_width = side == kBorderBefore
-                                         ? col->Style()->BorderBeforeWidth()
-                                         : col->Style()->BorderAfterWidth();
-      if (col_border_style == EBorderStyle::kHidden ||
-          cell_border_style == EBorderStyle::kHidden)
-        continue;
-      all_hidden = false;
-      if (ComputedStyle::BorderStyleIsVisible(col_border_style) &&
-          col_border_width > border_width)
-        border_width = col_border_width;
-      if (ComputedStyle::BorderStyleIsVisible(cell_border_style) &&
-          cell_border_width > border_width)
-        border_width = cell_border_width;
-    } else {
-      if (cell_border_style == EBorderStyle::kHidden)
-        continue;
-      all_hidden = false;
-      if (ComputedStyle::BorderStyleIsVisible(cell_border_style) &&
-          cell_border_width > border_width)
-        border_width = cell_border_width;
-    }
-  }
-  if (all_hidden)
-    return -1;
-
-  if (side == kBorderAfter)
-    border_width++;  // Distribute rounding error
-  return border_width / 2;
-}
-
-int LayoutTableSection::CalcInlineDirectionOuterBorder(
-    InlineBorderSide side) const {
-  unsigned total_cols = Table()->NumEffectiveColumns();
-  if (!grid_.size() || !total_cols)
-    return 0;
-  unsigned col_index = side == kBorderStart ? 0 : total_cols - 1;
-
-  int border_width = 0;
-
-  EBorderStyle section_border_style = side == kBorderStart
-                                          ? Style()->BorderStartStyle()
-                                          : Style()->BorderEndStyle();
-  const float section_border_width = side == kBorderStart
-                                         ? Style()->BorderStartWidth()
-                                         : Style()->BorderEndWidth();
-  if (section_border_style == EBorderStyle::kHidden)
-    return -1;
-  if (ComputedStyle::BorderStyleIsVisible(section_border_style))
-    border_width = section_border_width;
-
-  if (LayoutTableCol* col = Table()
-                                ->ColElementAtAbsoluteColumn(col_index)
-                                .InnermostColOrColGroup()) {
-    EBorderStyle col_border_style = side == kBorderStart
-                                        ? col->Style()->BorderStartStyle()
-                                        : col->Style()->BorderEndStyle();
-    const float col_border_width = side == kBorderStart
-                                       ? col->Style()->BorderStartWidth()
-                                       : col->Style()->BorderEndWidth();
-    if (col_border_style == EBorderStyle::kHidden)
-      return -1;
-    if (ComputedStyle::BorderStyleIsVisible(col_border_style) &&
-        col_border_width > border_width)
-      border_width = col_border_width;
-  }
-
-  bool all_hidden = true;
-  for (unsigned r = 0; r < grid_.size(); r++) {
-    if (col_index >= NumCols(r))
-      continue;
-    const auto& grid_cell = GridCellAt(r, col_index);
-    if (!grid_cell.HasCells())
-      continue;
-    // FIXME: Don't repeat for the same cell
-    const ComputedStyle& primary_cell_style =
-        grid_cell.PrimaryCell()->StyleRef();
-    const ComputedStyle& primary_cell_parent_style =
-        grid_cell.PrimaryCell()->Parent()->StyleRef();
-    // FIXME: Make this work with perpendicular and flipped cells.
-    EBorderStyle cell_border_style = side == kBorderStart
-                                         ? primary_cell_style.BorderStartStyle()
-                                         : primary_cell_style.BorderEndStyle();
-    EBorderStyle row_border_style =
-        side == kBorderStart ? primary_cell_parent_style.BorderStartStyle()
-                             : primary_cell_parent_style.BorderEndStyle();
-    const float cell_border_width = side == kBorderStart
-                                        ? primary_cell_style.BorderStartWidth()
-                                        : primary_cell_style.BorderEndWidth();
-    const float row_border_width =
-        side == kBorderStart ? primary_cell_parent_style.BorderStartWidth()
-                             : primary_cell_parent_style.BorderEndWidth();
-    if (cell_border_style == EBorderStyle::kHidden ||
-        row_border_style == EBorderStyle::kHidden)
-      continue;
-    all_hidden = false;
-    if (ComputedStyle::BorderStyleIsVisible(cell_border_style) &&
-        cell_border_width > border_width)
-      border_width = cell_border_width;
-    if (ComputedStyle::BorderStyleIsVisible(row_border_style) &&
-        row_border_width > border_width)
-      border_width = row_border_width;
-  }
-  if (all_hidden)
-    return -1;
-
-  if ((side == kBorderStart) != Table()->Style()->IsLeftToRightDirection())
-    border_width++;  // Distribute rounding error
-  return border_width / 2;
-}
-
-void LayoutTableSection::RecalcOuterBorder() {
-  outer_border_before_ = CalcBlockDirectionOuterBorder(kBorderBefore);
-  outer_border_after_ = CalcBlockDirectionOuterBorder(kBorderAfter);
-  outer_border_start_ = CalcInlineDirectionOuterBorder(kBorderStart);
-  outer_border_end_ = CalcInlineDirectionOuterBorder(kBorderEnd);
-}
-
 int LayoutTableSection::FirstLineBoxBaseline() const {
   if (!grid_.size())
     return -1;

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

@@ -204,17 +204,6 @@ class CORE_EXPORT LayoutTableSection final : public LayoutTableBoxComponent {
   void AppendEffectiveColumn(unsigned pos);
   void SplitEffectiveColumn(unsigned pos, unsigned first);
 
-  enum BlockBorderSide { kBorderBefore, kBorderAfter };
-  int CalcBlockDirectionOuterBorder(BlockBorderSide) const;
-  enum InlineBorderSide { kBorderStart, kBorderEnd };
-  int CalcInlineDirectionOuterBorder(InlineBorderSide) const;
-  void RecalcOuterBorder();
-
-  int OuterBorderBefore() const { return outer_border_before_; }
-  int OuterBorderAfter() const { return outer_border_after_; }
-  int OuterBorderStart() const { return outer_border_start_; }
-  int OuterBorderEnd() const { return outer_border_end_; }
-
   unsigned NumRows() const {
     DCHECK(!NeedsCellRecalc());
     return grid_.size();
@@ -439,11 +428,6 @@ class CORE_EXPORT LayoutTableSection final : public LayoutTableBoxComponent {
   unsigned c_col_;
   unsigned c_row_;
 
-  int outer_border_start_;
-  int outer_border_end_;
-  int outer_border_before_;
-  int outer_border_after_;
-
   bool needs_cell_recalc_;
 
   // This HashSet holds the overflowing cells for the partial paint path. If we

third_party/WebKit/Source/core/layout/LayoutTableTest.cpp

+// Copyright 2017 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/layout/LayoutTable.h"
+
+#include "core/layout/LayoutTestHelper.h"
+
+namespace blink {
+
+namespace {
+
+class LayoutTableTest : public RenderingTest {
+ protected:
+  LayoutTable* GetTableByElementId(const char* id) {
+    return ToLayoutTable(GetLayoutObjectByElementId(id));
+  }
+};
+
+TEST_F(LayoutTableTest, OverflowWithCollapsedBorders) {
+  SetBodyInnerHTML(
+      "<style>"
+      "  table { border-collapse: collapse }"
+      "  td { border: 0px solid blue; padding: 0 }"
+      "  div { width: 100px; height: 100px }"
+      "</style>"
+      "<table id='table'>"
+      "  <tr>"
+      "    <td style='border-bottom-width: 10px;"
+      "        outline: 3px solid blue'><div></div></td>"
+      "    <td style='border-width: 3px 15px'><div></div></td>"
+      "  </tr>"
+      "  <tr style='outline: 8px solid green'><td><div></div></td></tr>"
+      "</table>");
+
+  auto* table = GetTableByElementId("table");
+
+  // The table's self visual overflow covers the collapsed borders.
+  EXPECT_EQ(LayoutRect(0, 0, 230, 211), table->BorderBoxRect());
+  EXPECT_EQ(LayoutRect(0, 0, 230, 211), table->SelfVisualOverflowRect());
+
+  // The table's visual overflow covers self visual overflow and content visual
+  // overflows.
+  LayoutRect expected_visual_overflow = table->ContentBoxRect();
+  expected_visual_overflow.ExpandEdges(LayoutUnit(3), LayoutUnit(8),
+                                       LayoutUnit(8), LayoutUnit(8));
+  EXPECT_EQ(expected_visual_overflow, table->VisualOverflowRect());
+
+  // Tables layout overflow equals visual overflow.
+  EXPECT_EQ(expected_visual_overflow, table->LayoutOverflowRect());
+}
+
+TEST_F(LayoutTableTest, CollapsedBorders) {
+  SetBodyInnerHTML(
+      "<style>table { border-collapse: collapse }</style>"
+      "<table id='table1'"
+      "    style='border-top: hidden; border-bottom: 8px solid;"
+      "           border-left: hidden; border-right: 10px solid'>"
+      "  <tr><td>A</td><td>B</td></tr>"
+      "</table>"
+      "<table id='table2' style='border: 10px solid'>"
+      "  <tr>"
+      "    <td style='border: hidden'>C</td>"
+      "    <td style='border: hidden'>D</td>"
+      "  </tr>"
+      "</table>"
+      "<table id='table3' style='border: 10px solid'>"
+      "  <tr>"
+      "    <td style='border-top: 15px solid;"
+      "               border-left: 21px solid'>E</td>"
+      "    <td style='border-right: 25px solid'>F</td>"
+      "  </tr>"
+      // The second row won't affect start and end borders of the table.
+      "  <tr>"
+      "    <td style='border: 30px solid'>G</td>"
+      "    <td style='border: 40px solid'>H</td>"
+      "  </tr>"
+      "</table>");
+
+  auto* table1 = GetTableByElementId("table1");
+  EXPECT_EQ(0, table1->BorderBefore());
+  EXPECT_EQ(4, table1->BorderAfter());
+  EXPECT_EQ(0, table1->BorderStart());
+  EXPECT_EQ(5, table1->BorderEnd());
+
+  // All cells have hidden border.
+  auto* table2 = GetTableByElementId("table2");
+  EXPECT_EQ(0, table2->BorderBefore());
+  EXPECT_EQ(0, table2->BorderAfter());
+  EXPECT_EQ(0, table2->BorderStart());
+  EXPECT_EQ(0, table2->BorderEnd());
+
+  // Cells have wider borders.
+  auto* table3 = GetTableByElementId("table3");
+  // Cell E's border-top won.
+  EXPECT_EQ(7, table3->BorderBefore());
+  // Cell H's border-bottom won.
+  EXPECT_EQ(20, table3->BorderAfter());
+  // Cell E's border-left won.
+  EXPECT_EQ(10, table3->BorderStart());
+  // Cell F's border-bottom won.
+  EXPECT_EQ(13, table3->BorderEnd());
+}
+
+TEST_F(LayoutTableTest, CollapsedBordersWithCol) {
+  SetBodyInnerHTML(
+      "<style>table { border-collapse: collapse }</style>"
+      "<table id='table1' style='border: hidden'>"
+      "  <colgroup>"
+      "    <col span='2000' style='border: 10px solid'>"
+      "    <col span='2000' style='border: 20px solid'>"
+      "  </colgroup>"
+      "  <tr>"
+      "    <td colspan='2000'>A</td>"
+      "    <td colspan='2000'>B</td>"
+      "  </tr>"
+      "</table>"
+      "<table id='table2' style='border: 10px solid'>"
+      "  <colgroup>"
+      "    <col span='2000' style='border: 10px solid'>"
+      "    <col span='2000' style='border: 20px solid'>"
+      "  </colgroup>"
+      "  <tr>"
+      "    <td colspan='2000' style='border: hidden'>C</td>"
+      "    <td colspan='2000' style='border: hidden'>D</td>"
+      "  </tr>"
+      "</table>"
+      "<table id='table3'>"
+      "  <colgroup>"
+      "    <col span='2000' style='border: 10px solid'>"
+      "    <col span='2000' style='border: 20px solid'>"
+      "  </colgroup>"
+      "  <tr>"
+      "    <td colspan='2000' style='border: 12px solid'>E</td>"
+      "    <td colspan='2000' style='border: 16px solid'>F</td>"
+      "  </tr>"
+      "</table>");
+
+  // Table has hidden border.
+  auto* table1 = GetTableByElementId("table1");
+  EXPECT_EQ(0, table1->BorderBefore());
+  EXPECT_EQ(0, table1->BorderAfter());
+  EXPECT_EQ(0, table1->BorderStart());
+  EXPECT_EQ(0, table1->BorderEnd());
+
+  // All cells have hidden border.
+  auto* table2 = GetTableByElementId("table2");
+  EXPECT_EQ(0, table2->BorderBefore());
+  EXPECT_EQ(0, table2->BorderAfter());
+  EXPECT_EQ(0, table2->BorderStart());
+  EXPECT_EQ(0, table2->BorderEnd());
+
+  // Combined cell and col borders.
+  auto* table3 = GetTableByElementId("table3");
+  // The second col's border-top won.
+  EXPECT_EQ(10, table3->BorderBefore());
+  // The second col's border-bottom won.
+  EXPECT_EQ(10, table3->BorderAfter());
+  // Cell E's border-left won.
+  EXPECT_EQ(6, table3->BorderStart());
+  // The second col's border-right won.
+  EXPECT_EQ(10, table3->BorderEnd());
+}
+
+}  // anonymous namespace
+
+}  // namespace blink