Merge pull request #2743 from ctiller/ampidextrous-parrot

Switch ALPN/NPN to advertise only h2

src/core/transport/chttp2/alpn.c

@@ -36,8 +36,7 @@
 #include <grpc/support/useful.h>
 
 /* in order of preference */
-static const char *const supported_versions[] = {"h2", "h2-17", "h2-16",
-                                                 "h2-15", "h2-14"};
+static const char *const supported_versions[] = {"h2"};
 
 int grpc_chttp2_is_alpn_version_supported(const char *version, size_t size) {
   size_t i;