Add ALTS fuzzer
diff --git a/grpc.gyp b/grpc.gyp
index 0c567d9..fff7c53 100644
--- a/grpc.gyp
+++ b/grpc.gyp
@@ -577,6 +577,7 @@
         'test/core/end2end/fixtures/proxy.cc',
         'test/core/iomgr/endpoint_tests.cc',
         'test/core/util/debugger_macros.cc',
+        'test/core/util/fuzzer_util.cc',
         'test/core/util/grpc_profiler.cc',
         'test/core/util/histogram.cc',
         'test/core/util/memory_counters.cc',
@@ -807,6 +808,7 @@
         'test/core/end2end/fixtures/proxy.cc',
         'test/core/iomgr/endpoint_tests.cc',
         'test/core/util/debugger_macros.cc',
+        'test/core/util/fuzzer_util.cc',
         'test/core/util/grpc_profiler.cc',
         'test/core/util/histogram.cc',
         'test/core/util/memory_counters.cc',