Make string_util::WriteInto() DCHECK() that the supplied |length_with_null| > 1, meaning that the...

base/rand_util.h

Index: base/rand_util.h
===================================================================
--- base/rand_util.h	(revision 107404)
+++ base/rand_util.h	(working copy)
@@ -38,9 +38,9 @@
 BASE_EXPORT void RandBytes(void* output, size_t output_length);
 
 // Fills a string of length |length| with with cryptographically strong random
-// data and returns it.
+// data and returns it.  |length| should be nonzero.
 //
-// Not that this is a variation of |RandBytes| with a different return type.
+// Note that this is a variation of |RandBytes| with a different return type.
 BASE_EXPORT std::string RandBytesAsString(size_t length);
 
 }  // namespace base