Making LayoutUnit conversions to Float type explicit

Source/core/rendering/RenderMultiColumnSet.h

 /*
  * Copyright (C) 2012 Apple Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 143 matching lines @@
         ContentRun(LayoutUnit breakOffset)
             : m_breakOffset(breakOffset)
             , m_assumedImplicitBreaks(0) { }
 
         unsigned assumedImplicitBreaks() const { return m_assumedImplicitBreaks; }
         void assumeAnotherImplicitBreak() { m_assumedImplicitBreaks++; }
         LayoutUnit breakOffset() const { return m_breakOffset; }
 
         // Return the column height that this content run would require, considering the implicit
         // breaks assumed so far.
-        LayoutUnit columnLogicalHeight(LayoutUnit startOffset) const { return ceilf(float(m_breakOffset - startOffset) / float(m_assumedImplicitBreaks + 1)); }
+        LayoutUnit columnLogicalHeight(LayoutUnit startOffset) const { return ceilf((m_breakOffset - startOffset).toFloat() / float(m_assumedImplicitBreaks + 1)); }
 
     private:
         LayoutUnit m_breakOffset; // Flow thread offset where this run ends.
         unsigned m_assumedImplicitBreaks; // Number of implicit breaks in this run assumed so far.
     };
     Vector<ContentRun, 1> m_contentRuns;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderMultiColumnSet, isRenderMultiColumnSet());
 
 } // namespace WebCore
 
 #endif // RenderMultiColumnSet_h