Respect break-inside:avoid on table rows

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

Index: third_party/WebKit/Source/core/layout/LayoutTableSection.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutTableSection.cpp b/third_party/WebKit/Source/core/layout/LayoutTableSection.cpp
index 89b925af6f41a1551f1d609cd14bd23c85fada16..1045bb60d5a55f6a07973facd1b42397794927e1 100644
--- a/third_party/WebKit/Source/core/layout/LayoutTableSection.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutTableSection.cpp
@@ -965,6 +965,7 @@ void LayoutTableSection::layoutRows()
     for (unsigned r = 0; r < totalRows; r++) {
         // Set the row's x/y position and width/height.
         LayoutTableRow* rowLayoutObject = m_grid[r].rowLayoutObject;
+        int paginationStrutOnRow = 0;
         if (rowLayoutObject) {
             rowLayoutObject->setLocation(LayoutPoint(0, m_rowPos[r]));
             rowLayoutObject->setLogicalWidth(logicalWidth());
@@ -972,6 +973,11 @@ void LayoutTableSection::layoutRows()
             rowLayoutObject->updateLayerTransformAfterLayout();
             rowLayoutObject->clearAllOverflows();
             rowLayoutObject->addVisualEffectOverflow();
+            if (view()->layoutState()->isPaginated()) {

[mstensho (USE GERRIT), 2016/03/29 09:57:46]

Might want to cache this on the outside of the loop.

+                paginationStrutOnRow = getPaginationStrutForRow(rowLayoutObject, LayoutUnit(m_rowPos[r]));
+                for (unsigned rowIndex = r; paginationStrutOnRow && rowIndex <= totalRows; rowIndex++)
+                    m_rowPos[rowIndex] += paginationStrutOnRow;
+            }
         }
 
         int rowHeightIncreaseForPagination = 0;
@@ -1051,7 +1057,7 @@ void LayoutTableSection::layoutRows()
             cell->layoutIfNeeded();
 
             // FIXME: Make pagination work with vertical tables.
-            if (view()->layoutState()->pageLogicalHeight() && cell->logicalHeight() != rHeight) {
+            if (!paginationStrutOnRow && view()->layoutState()->pageLogicalHeight() && cell->logicalHeight() != rHeight) {
                 // FIXME: Pagination might have made us change size. For now just shrink or grow the cell to fit without doing a relayout.
                 // We'll also do a basic increase of the row height to accommodate the cell if it's bigger, but this isn't quite right
                 // either. It's at least stable though and won't result in an infinite # of relayouts that may never stabilize.
@@ -1095,6 +1101,29 @@ void LayoutTableSection::layoutRows()
     computeOverflowFromCells(totalRows, nEffCols);
 }
 
+int LayoutTableSection::getPaginationStrutForRow(LayoutTableRow* row, LayoutUnit logicalOffset) const
+{
+    if (row->getPaginationBreakability() == AllowAnyBreaks)
+        return 0;
+    LayoutUnit pageLogicalHeight = pageLogicalHeightForOffset(logicalOffset);
+    if (!pageLogicalHeight)
+        return 0;
+    // If the row is too tall for the page don't insert a strut.
+    LayoutUnit rowLogicalHeight = row->logicalHeight();
+    if (rowLogicalHeight > pageLogicalHeight)
+        return 0;
+    LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(logicalOffset, LayoutBlock::AssociateWithLatterPage);
+    if (remainingLogicalHeight >= rowLogicalHeight)
+        return 0; // It fits fine where it is. No need to break.
+    LayoutUnit paginationStrut = calculatePaginationStrutToFitContent(logicalOffset, remainingLogicalHeight, rowLogicalHeight);
+    if (paginationStrut == remainingLogicalHeight && remainingLogicalHeight == pageLogicalHeight) {
+        // Don't break if we were at the top of a page, and we failed to fit the content
+        // completely. No point in leaving a page completely blank.
+        return 0;
+    }
+    return paginationStrut;
+}
+
 void LayoutTableSection::computeOverflowFromCells()
 {
     unsigned totalRows = m_grid.size();