Disallow cast/implicit conversion from LayoutUnit to int/unsigned

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

Index: third_party/WebKit/Source/core/layout/LayoutMultiColumnFlowThread.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutMultiColumnFlowThread.cpp b/third_party/WebKit/Source/core/layout/LayoutMultiColumnFlowThread.cpp
index f5ffc24d23a67de54242fc8159fadfca3ca86669..2bc45e6ac51721f57ac3ba6a33a4c132b03c3d3c 100644
--- a/third_party/WebKit/Source/core/layout/LayoutMultiColumnFlowThread.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutMultiColumnFlowThread.cpp
@@ -585,10 +585,11 @@ void LayoutMultiColumnFlowThread::calculateColumnCountAndWidth(LayoutUnit& width
         count = computedColumnCount;
         width = ((availableWidth - ((count - 1) * columnGap)) / count).clampNegativeToZero();
     } else if (!columnStyle->hasAutoColumnWidth() && columnStyle->hasAutoColumnCount()) {
-        count = std::max(LayoutUnit(1), (availableWidth + columnGap) / (computedColumnWidth + columnGap));
+        count = std::max(LayoutUnit(1), (availableWidth + columnGap) / (computedColumnWidth + columnGap)).toUnsigned();
         width = ((availableWidth + columnGap) / count) - columnGap;
     } else {
-        count = std::max(std::min(LayoutUnit(computedColumnCount), (availableWidth + columnGap) / (computedColumnWidth + columnGap)), LayoutUnit(1));
+        count = std::max(std::min(LayoutUnit(computedColumnCount), (availableWidth + columnGap) / (computedColumnWidth + columnGap)), LayoutUnit(1)).toUnsigned();
+        count = std::max(count, 1u);

[mstensho (USE GERRIT), 2016/08/22 18:05:17]

What's this for? The line above already makes sure that it's at least
LayoutUnit(1), doesn't it?

[Xianzhu, 2016/08/22 18:15:37]

Thanks for the catch. This is garbage left from previous versions of the CL.
Removed.

         width = ((availableWidth + columnGap) / count) - columnGap;
     }
 }