Handle exclusive end offsets when translating from flow thread coordinates.

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

Index: third_party/WebKit/Source/core/layout/ColumnBalancer.cpp
diff --git a/third_party/WebKit/Source/core/layout/ColumnBalancer.cpp b/third_party/WebKit/Source/core/layout/ColumnBalancer.cpp
index 5e642990b39485765110ff957488b5204195e540..4317e625a8f4d3c2698adbffc6c3dcab85760d4e 100644
--- a/third_party/WebKit/Source/core/layout/ColumnBalancer.cpp
+++ b/third_party/WebKit/Source/core/layout/ColumnBalancer.cpp
@@ -165,7 +165,7 @@ void InitialColumnHeightFinder::recordStrutBeforeOffset(LayoutUnit offsetInFlowT
     ASSERT(columnSet().usedColumnCount() >= 1);
     unsigned columnCount = columnSet().usedColumnCount();
     ASSERT(m_shortestStruts.size() == columnCount);
-    unsigned index = groupAtOffset(offsetInFlowThread).columnIndexAtOffset(offsetInFlowThread - strut, MultiColumnFragmentainerGroup::AssumeNewColumns);
+    unsigned index = groupAtOffset(offsetInFlowThread).columnIndexAtOffset(offsetInFlowThread - strut, LayoutBox::AssociateWithLatterPage);
     if (index >= columnCount)
         return;
     m_shortestStruts[index] = std::min(m_shortestStruts[index], strut);
@@ -173,7 +173,7 @@ void InitialColumnHeightFinder::recordStrutBeforeOffset(LayoutUnit offsetInFlowT
 
 LayoutUnit InitialColumnHeightFinder::spaceUsedByStrutsAt(LayoutUnit offsetInFlowThread) const
 {
-    unsigned stopBeforeColumn = groupAtOffset(offsetInFlowThread).columnIndexAtOffset(offsetInFlowThread, MultiColumnFragmentainerGroup::AssumeNewColumns) + 1;
+    unsigned stopBeforeColumn = groupAtOffset(offsetInFlowThread).columnIndexAtOffset(offsetInFlowThread, LayoutBox::AssociateWithLatterPage) + 1;
     stopBeforeColumn = std::min(stopBeforeColumn, columnSet().usedColumnCount());
     ASSERT(stopBeforeColumn <= m_shortestStruts.size());
     LayoutUnit totalStrutSpace;