Allow enabling of each filter

src/core/ext/filters/workarounds/workaround_cronet_compression_filter.c

@@ -206,6 +206,9 @@ const grpc_channel_filter grpc_workaround_cronet_compression_filter = {
 
 static bool register_workaround_cronet_compression(
     grpc_exec_ctx* exec_ctx, grpc_channel_stack_builder* builder, void* arg) {
+  if (!grpc_workaround_is_enabled(GRPC_WORKAROUND_ID_CRONET_COMPRESSION)) {
+    return true;
+  }
   grpc_register_workaround(GRPC_WORKAROUND_ID_CRONET_COMPRESSION,
                            parse_user_agent);
   return grpc_channel_stack_builder_prepend_filter(

src/core/ext/filters/workarounds/workaround_utils.c

@@ -36,6 +36,14 @@
 
 static user_agent_parser user_agent_parsers[GRPC_MAX_WORKAROUND_ID];
 
+/* Workarounds enabled by user */
+static bool workaround_enabled[GRPC_MAX_WORKAROUND_ID];
+
+/* Workarounds supported by C core */
+static bool workaround_supported[GRPC_MAX_WORKAROUND_ID] = {
+  true    /* GRPC_WORKAROUND_ID_CRONET_COMPRESSION */
+};
+
 grpc_user_agent_md *grpc_parse_user_agent(grpc_mdelem md) {
   grpc_user_agent_md *user_agent_md;
 
@@ -55,3 +63,17 @@ void grpc_register_workaround(uint32_t id, user_agent_parser parser) {
   GPR_ASSERT(id < GRPC_MAX_WORKAROUND_ID);
   user_agent_parsers[id] = parser;
 }
+
+bool grpc_workaround_is_enabled(uint32_t id) {
+  GPR_ASSERT(id < GRPC_MAX_WORKAROUND_ID);
+  return workaround_enabled[id];
+}
+
+bool grpc_enable_workaround(uint32_t id) {
+  if (workaround_supported[id]) {
+    workaround_enabled[id] = true;
+    return true;
+  } else {
+    return false;
+  }
+}

src/core/ext/filters/workarounds/workaround_utils.h

@@ -51,4 +51,6 @@ typedef bool (*user_agent_parser)(grpc_mdelem);
 
 void grpc_register_workaround(uint32_t id, user_agent_parser parser);
 
+bool grpc_workaround_is_enabled(uint32_t id);
+
 #endif