Disallow cast/implicit conversion from LayoutUnit to int/unsigned

third_party/WebKit/Source/platform/LayoutUnit.h

Index: third_party/WebKit/Source/platform/LayoutUnit.h
diff --git a/third_party/WebKit/Source/platform/LayoutUnit.h b/third_party/WebKit/Source/platform/LayoutUnit.h
index 700aef96bd08df3423fe5895456321b7f03893b8..cff94492f6c2c4f9f7ab2b1c8fb6633a41faa4f1 100644
--- a/third_party/WebKit/Source/platform/LayoutUnit.h
+++ b/third_party/WebKit/Source/platform/LayoutUnit.h
@@ -107,8 +107,12 @@ public:
     }
     unsigned toUnsigned() const { REPORT_OVERFLOW(m_value >= 0); return toInt(); }
 
-    operator int() const { return toInt(); }
-    operator unsigned() const { return toUnsigned(); }
+    // Conversion to int or unsigned is lossy. 'explicit' on these operators won't work because
+    // there are also other implicit conversion paths (e.g. operator bool then to int which would
+    // generate wrong result). Use toInt() and toUnsigned() instead.
+    operator int() const = delete;
+    operator unsigned() const = delete;
+
     operator double() const { return toDouble(); }
     operator float() const { return toFloat(); }
     operator bool() const { return m_value; }