Use implicit_cast<> instead of static_cast<> whenever possible

util/numeric/checked_range.h

Index: util/numeric/checked_range.h
diff --git a/util/numeric/checked_range.h b/util/numeric/checked_range.h
index df3e395fe2be334ae5615d86ff4eb3d2ee9b0046..982ee4f2af752d6d2e7ba630fb1649c80aed3420 100644
--- a/util/numeric/checked_range.h
+++ b/util/numeric/checked_range.h
@@ -63,7 +63,7 @@ class CheckedRange {
       return false;
     }
     base::CheckedNumeric<ValueType> checked_end(base_);
-    checked_end += static_cast<ValueType>(size_);
+    checked_end += implicit_cast<ValueType>(size_);
     return checked_end.IsValid();
   }