Make column snapping optional when translating to flow thread coordinates.

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

Index: third_party/WebKit/Source/core/layout/LayoutMultiColumnSet.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutMultiColumnSet.cpp b/third_party/WebKit/Source/core/layout/LayoutMultiColumnSet.cpp
index 7d251344bb3c5ea25451bd41e06cfeb678ccf201..6044f69169fe3fa7d924520e3e87119b918052b2 100644
--- a/third_party/WebKit/Source/core/layout/LayoutMultiColumnSet.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutMultiColumnSet.cpp
@@ -474,8 +474,9 @@ PositionWithAffinity LayoutMultiColumnSet::positionForPoint(
   // Convert the visual point to a flow thread point.
   const MultiColumnFragmentainerGroup& row =
       fragmentainerGroupAtVisualPoint(point);
-  LayoutPoint flowThreadPoint =
-      row.visualPointToFlowThreadPoint(point + row.offsetFromColumnSet());
+  LayoutPoint flowThreadPoint = row.visualPointToFlowThreadPoint(
+      point + row.offsetFromColumnSet(),
+      MultiColumnFragmentainerGroup::SnapToColumn);
   // Then drill into the flow thread, where we'll find the actual content.
   return flowThread()->positionForPoint(flowThreadPoint);
 }