Add fuzzer for FlexfecSender.

webrtc/test/fuzzers/BUILD.gn

Index: webrtc/test/fuzzers/BUILD.gn
diff --git a/webrtc/test/fuzzers/BUILD.gn b/webrtc/test/fuzzers/BUILD.gn
index 764d71917f1d3c41313b233dfd3ae0c0ae6eebca..57a40a6fbabae0cb7753a5ecf4be245a239ffb78 100644
--- a/webrtc/test/fuzzers/BUILD.gn
+++ b/webrtc/test/fuzzers/BUILD.gn
@@ -77,6 +77,16 @@ webrtc_fuzzer_test("flexfec_header_reader_fuzzer") {
   ]
 }
 
+webrtc_fuzzer_test("flexfec_sender_fuzzer") {
+  sources = [
+    "flexfec_sender_fuzzer.cc",
+  ]
+  deps = [
+    "../../modules/rtp_rtcp/",
+  ]
+  libfuzzer_options = [ "max_len=200" ]
+}
+
 webrtc_fuzzer_test("ulpfec_header_reader_fuzzer") {
   sources = [
     "ulpfec_header_reader_fuzzer.cc",