Remove unused QuicVersionManager::disable_version_q050().

PiperOrigin-RevId: 395246360
diff --git a/quic/core/quic_version_manager.cc b/quic/core/quic_version_manager.cc
index 42a1630..a7b7426 100644
--- a/quic/core/quic_version_manager.cc
+++ b/quic/core/quic_version_manager.cc
@@ -105,9 +105,4 @@
   filtered_supported_alpns_.push_back(alpn);
 }
 
-bool QuicVersionManager::disable_version_q050() const {
-  return lazy_ ? GetQuicReloadableFlag(quic_disable_version_q050)
-               : disable_version_q050_;
-}
-
 }  // namespace quic
diff --git a/quic/core/quic_version_manager.h b/quic/core/quic_version_manager.h
index 0ffede5..487d057 100644
--- a/quic/core/quic_version_manager.h
+++ b/quic/core/quic_version_manager.h
@@ -53,10 +53,6 @@
   // Must not be called elsewhere.
   void AddCustomAlpn(const std::string& alpn);
 
-  // TODO(dschinazi): Remove when deprecating
-  // FLAGS_gfe2_restart_flag_quic_disable_old_alt_svc_format.
-  bool disable_version_q050() const;
-
  private:
   // Cached value of gfe2_restart_flag_quic_lazy_quic_version_manager for
   // brevity.