Remove GFE2-specific comments from Balsa.

PiperOrigin-RevId: 445121945

quiche/common/balsa/balsa_headers.h

diff --git a/quiche/common/balsa/balsa_headers.h b/quiche/common/balsa/balsa_headers.h
index 3a00577..38caace 100644
--- a/quiche/common/balsa/balsa_headers.h
+++ b/quiche/common/balsa/balsa_headers.h
@@ -396,9 +396,9 @@
     IteratorType begin_iterator_, end_iterator_;
   };
 
-  // Set of names of headers that might have multiple values. The GFE2 and
-  // Envoy/GFE3 use different sets, and CoalesceOption::kCoalesce can be used
-  // to match Envoy behavior in WriteToBuffer().
+  // Set of names of headers that might have multiple values.
+  // CoalesceOption::kCoalesce can be used to match Envoy behavior in
+  // WriteToBuffer().
   using MultivaluedHeadersSet =
       absl::flat_hash_set<absl::string_view, StringPieceCaseHash,
                           StringPieceCaseEqual>;