Simpler repro of DCHECK badness in release builds.

net/base/lookup_string_in_fixed_set.cc

Index: net/base/lookup_string_in_fixed_set.cc
diff --git a/net/base/lookup_string_in_fixed_set.cc b/net/base/lookup_string_in_fixed_set.cc
index 46497f3c47bb654c44e6aa34f9b72a2fd5820fb9..bcf9246dda82b15954cfb85ee33448a799e1b172 100644
--- a/net/base/lookup_string_in_fixed_set.cc
+++ b/net/base/lookup_string_in_fixed_set.cc
@@ -96,6 +96,7 @@ int LookupStringInFixedSet(const unsigned char* graph,
   const unsigned char* offset = pos;
   const char* key_end = key + key_length;
   while (GetNextOffset(&pos, end, &offset)) {
+    DCHECK((pos == nullptr) || pos < end);
     //   char <char>+ end_char offsets
     //   char <char>+ return value
     //   char end_char offsets