Issue #146 - Part 1: Draw each table's background on their own display

list items.

This patch does the following things:
1. Creates nsDisplayTableBorderCollapse that draws all collapse border
of tables.
2. Stops the use of nsDisplayTableBorderBackground.
3. Lets column and column group frames generate display items.
4. When traversing the table, also traverses the column and column group
frames.
5. For each type of table frame (col group, col, row group, row and
cell), draws their own background.

1 files changed, 42 insertions, 61 deletions

diff --git a/layout/tables/nsTableCellFrame.cpp b/layout/tables/nsTableCellFrame.cpp
index dea82ea59..bac8d387f 100644
--- a/layout/tables/nsTableCellFrame.cpp
+++ b/layout/tables/nsTableCellFrame.cpp
@@ -484,70 +484,51 @@ nsTableCellFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                                    const nsDisplayListSet& aLists)
 {
   DO_GLOBAL_REFLOW_COUNT_DSP("nsTableCellFrame");
-  if (IsVisibleInSelection(aBuilder)) {
-    nsTableFrame* tableFrame = GetTableFrame();
-    int32_t emptyCellStyle = GetContentEmpty() && !tableFrame->IsBorderCollapse() ?
-                                StyleTableBorder()->mEmptyCells
-                                : NS_STYLE_TABLE_EMPTY_CELLS_SHOW;
-    // take account of 'empty-cells'
-    if (StyleVisibility()->IsVisible() &&
-        (NS_STYLE_TABLE_EMPTY_CELLS_HIDE != emptyCellStyle)) {
-      // display outset box-shadows if we need to.
-      bool hasBoxShadow = !!StyleEffects()->mBoxShadow;
-      if (hasBoxShadow) {
-        aLists.BorderBackground()->AppendNewToTop(
-          new (aBuilder) nsDisplayBoxShadowOuter(aBuilder, this));
-      }
-    
-      // display background if we need to.
-      if (aBuilder->IsForEventDelivery() ||
-          !StyleBackground()->IsTransparent() || StyleDisplay()->mAppearance) {
-        if (!tableFrame->IsBorderCollapse()) {
-          nsDisplayBackgroundImage::AppendBackgroundItemsToTop(aBuilder,
-              this,
-              GetRectRelativeToSelf(),
-              aLists.BorderBackground());
-        } else if (aBuilder->IsAtRootOfPseudoStackingContext() ||
-                   aBuilder->IsForEventDelivery()) {
-          // The cell background was not painted by the nsTablePainter,
-          // so we need to do it. We have special background processing here
-          // so we need to duplicate some code from nsFrame::DisplayBorderBackgroundOutline
-          nsDisplayTableItem* item =
-            new (aBuilder) nsDisplayTableCellBackground(aBuilder, this);
-          aLists.BorderBackground()->AppendNewToTop(item);
-          item->UpdateForFrameBackground(this);
-        } else {
-          // The nsTablePainter will paint our background. Make sure it
-          // knows if we're background-attachment:fixed.
-          nsDisplayTableItem* currentItem = aBuilder->GetCurrentTableItem();
-          if (currentItem) {
-            currentItem->UpdateForFrameBackground(this);
-          }
-        }
-      }
-    
-      // display inset box-shadows if we need to.
-      if (hasBoxShadow) {
-        aLists.BorderBackground()->AppendNewToTop(
-          new (aBuilder) nsDisplayBoxShadowInner(aBuilder, this));
-      }
-    
-      // display borders if we need to
-      ProcessBorders(tableFrame, aBuilder, aLists);
-    
-      // and display the selection border if we need to
-      if (IsSelected()) {
-        aLists.BorderBackground()->AppendNewToTop(new (aBuilder)
-          nsDisplayGeneric(aBuilder, this, ::PaintTableCellSelection,
-                           "TableCellSelection",
-                           nsDisplayItem::TYPE_TABLE_CELL_SELECTION));
-      }
+  nsTableFrame* tableFrame = GetTableFrame();
+  int32_t emptyCellStyle = GetContentEmpty() && !tableFrame->IsBorderCollapse() ?
+                              StyleTableBorder()->mEmptyCells
+                              : NS_STYLE_TABLE_EMPTY_CELLS_SHOW;
+  // take account of 'empty-cells'
+  if (StyleVisibility()->IsVisible() &&
+      (NS_STYLE_TABLE_EMPTY_CELLS_HIDE != emptyCellStyle)) {
+    // display outset box-shadows if we need to.
+    bool hasBoxShadow = !!StyleEffects()->mBoxShadow;
+    if (hasBoxShadow) {
+      aLists.BorderBackground()->AppendNewToTop(
+        new (aBuilder) nsDisplayBoxShadowOuter(aBuilder, this));
+    }
+
+    // display background if we need to.
+    if (aBuilder->IsForEventDelivery() ||
+        !StyleBackground()->IsTransparent() ||
+        StyleDisplay()->mAppearance) {
+      nsDisplayBackgroundImage::AppendBackgroundItemsToTop(aBuilder,
+          this,
+          GetRectRelativeToSelf(),
+          aLists.BorderBackground());
+    }
+
+    // display inset box-shadows if we need to.
+    if (hasBoxShadow) {
+      aLists.BorderBackground()->AppendNewToTop(
+        new (aBuilder) nsDisplayBoxShadowInner(aBuilder, this));
+    }
+
+    // display borders if we need to
+    ProcessBorders(tableFrame, aBuilder, aLists);
+
+    // and display the selection border if we need to
+    if (IsSelected()) {
+      aLists.BorderBackground()->AppendNewToTop(new (aBuilder)
+        nsDisplayGeneric(aBuilder, this, ::PaintTableCellSelection,
+                         "TableCellSelection",
+                         nsDisplayItem::TYPE_TABLE_CELL_SELECTION));
     }
-    
-    // the 'empty-cells' property has no effect on 'outline'
-    DisplayOutline(aBuilder, aLists);
   }
 
+  // the 'empty-cells' property has no effect on 'outline'
+  DisplayOutline(aBuilder, aLists);
+
   // Push a null 'current table item' so that descendant tables can't
   // accidentally mess with our table
   nsAutoPushCurrentTableItem pushTableItem;