Table rows are incorrectly collapsed in case of hidden cells and rowspans.

Source/core/rendering/RenderTableSection.cpp

Index: Source/core/rendering/RenderTableSection.cpp
diff --git a/Source/core/rendering/RenderTableSection.cpp b/Source/core/rendering/RenderTableSection.cpp
index db5577a5ee73a23a31087ede0ce0427546e5471d..5fa44e29358ea09b5f5845e9a0d0bf5eb92884d7 100644
--- a/Source/core/rendering/RenderTableSection.cpp
+++ b/Source/core/rendering/RenderTableSection.cpp
@@ -544,7 +544,17 @@ void RenderTableSection::distributeRowSpanHeightToRows(SpanningRenderTableCells&
         if (spanningRowsHeight.rowWithOnlySpanningCells)
             updateRowsHeightHavingOnlySpanningCells(cell, spanningRowsHeight);
 
-        if (!spanningRowsHeight.totalRowsHeight || spanningRowsHeight.spanningCellHeightIgnoringBorderSpacing <= spanningRowsHeight.totalRowsHeight) {
+
+        if (!spanningRowsHeight.totalRowsHeight && spanningRowsHeight.spanningCellHeightIgnoringBorderSpacing) {
+            if (spanningRowsHeight.spanningCellHeightIgnoringBorderSpacing) {

[Julien - ping for review, 2013/10/30 18:12:44]

This 'if' is unneeded: to get into this branch, you have to satisfy the exact
same condition above.

[suchit.agrawal, 2013/10/31 13:43:02]

Previous condition is wrong. Forgot to remove it from there when it is added
inside. Thanks

+                spanningRowsHeight.totalRowsHeight = spanningRowsHeight.spanningCellHeightIgnoringBorderSpacing + borderSpacingForRow(rowIndex + rowSpan -1);

[Julien - ping for review, 2013/10/30 18:12:44]

Please add a comment about what this line is supposed to do. It seems like the
next branch will definitely be impacted by this line (you change
spanningRowsHeight.totalRowsHeight to be non-zero above).

Also why do we do it here and not when populating spanningRowsHeight?

[suchit.agrawal, 2013/10/31 13:43:02]

spanningRowsHeight.totalRowsHeight change is not required because just after
that continue is used.

+                m_rowPos[rowIndex + rowSpan] += spanningRowsHeight.totalRowsHeight;
+            }
+            extraHeightToPropagate = m_rowPos[rowIndex + rowSpan] - originalBeforePosition;
+            continue;
+        }
+
+        if (spanningRowsHeight.spanningCellHeightIgnoringBorderSpacing <= spanningRowsHeight.totalRowsHeight) {
             extraHeightToPropagate = m_rowPos[rowIndex + rowSpan] - originalBeforePosition;
             continue;
         }