Revert of Cleanup sign checking in safe math code

base/numerics/safe_math_impl.h

Index: base/numerics/safe_math_impl.h
diff --git a/base/numerics/safe_math_impl.h b/base/numerics/safe_math_impl.h
index f648d1642074f9071c66891e9bd2f4e8f7a7afb8..ae0a5b1d4f031d8228ee47172daf27153dd6ce77 100644
--- a/base/numerics/safe_math_impl.h
+++ b/base/numerics/safe_math_impl.h
@@ -47,8 +47,8 @@
 template <typename T>
 constexpr bool HasSignBit(T x) {
   // Cast to unsigned since right shift on signed is undefined.
-  return static_cast<typename std::make_signed<T>::type>(x) <
-         static_cast<typename std::make_signed<T>::type>(0);
+  return !!(static_cast<typename std::make_unsigned<T>::type>(x) >>
+            PositionOfSignBit<T>::value);
 }
 
 // This wrapper undoes the standard integer promotions.