Clean up PageBoundaryRule enum.

Source/core/layout/LayoutMultiColumnFlowThread.cpp

Index: Source/core/layout/LayoutMultiColumnFlowThread.cpp
diff --git a/Source/core/layout/LayoutMultiColumnFlowThread.cpp b/Source/core/layout/LayoutMultiColumnFlowThread.cpp
index 54027738a753e6e0107eb2e9ea4e6a0389d906ee..4e2041b5546e9daf9cd5d8394e4e43e356191e9a 100644
--- a/Source/core/layout/LayoutMultiColumnFlowThread.cpp
+++ b/Source/core/layout/LayoutMultiColumnFlowThread.cpp
@@ -910,7 +910,7 @@ bool LayoutMultiColumnFlowThread::addForcedColumnBreak(LayoutUnit offset, Layout
     if (LayoutMultiColumnSet* multicolSet = columnSetAtBlockOffset(offset)) {
         multicolSet->addContentRun(offset);
         if (offsetBreakAdjustment)
-            *offsetBreakAdjustment = pageLogicalHeightForOffset(offset) ? pageRemainingLogicalHeightForOffset(offset, IncludePageBoundary) : LayoutUnit();
+            *offsetBreakAdjustment = pageLogicalHeightForOffset(offset) ? pageRemainingLogicalHeightForOffset(offset, AssociateWithFormerPage) : LayoutUnit();
         return true;
     }
     return false;