Moving some config defaults to build.yaml, and moving others to CPPFLAGS.
diff --git a/src/boringssl/gen_build_yaml.py b/src/boringssl/gen_build_yaml.py
index b635ee4..7c7a579 100755
--- a/src/boringssl/gen_build_yaml.py
+++ b/src/boringssl/gen_build_yaml.py
@@ -82,6 +82,7 @@
               for f in files['ssl_headers'] + files['ssl_internal_headers'] + files['crypto_headers'] + files['crypto_internal_headers']
             ),
             'boringssl': True,
+            'defaults': 'boringssl',
           },
           {
             'name': 'boringssl_test_util',
@@ -89,6 +90,7 @@
             'language': 'c++',
             'secure': 'no',
             'boringssl': True,
+            'defaults': 'boringssl',
             'src': [
               map_dir(f)
               for f in sorted(files['test_support'])
@@ -103,6 +105,7 @@
             'src': [map_dir(test)],
             'vs_proj_dir': 'test/boringssl',
             'boringssl': True,
+            'defaults': 'boringssl',
             'deps': [
                 'boringssl_test_util',
                 'boringssl',
@@ -120,6 +123,7 @@
             'src': [],
             'vs_proj_dir': 'test/boringssl',
             'boringssl': True,
+            'defaults': 'boringssl',
             'deps': [
                 'boringssl_%s_lib' % os.path.splitext(os.path.basename(test))[0],
                 'boringssl_test_util',
@@ -138,6 +142,7 @@
             'flaky': False,
             'language': 'c++',
             'boringssl': True,
+            'defaults': 'boringssl',
             'cpu_cost': 1.0
           }
           for test in files['tests']