[Wconversion] Suppress warnings

Bug: 58162
Change-Id: I968862e87fe067af6fae22cb237694098bf6b7fe
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/grpc/+/426268
Reviewed-by: David Turner <digit@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 0d1167c..f3a4444 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1068,6 +1068,7 @@
     "//third_party/protobuf:protoc_lib",
   ]
 
+  configs += [ ":grpc_warnings" ]
   public_configs = [ ":grpc_config" ]
 }
 }
@@ -1083,6 +1084,7 @@
     "//third_party/protobuf:protoc_lib",
   ]
 
+  configs += [ ":grpc_warnings" ]
   configs += [ "//third_party/protobuf:protobuf_config" ]
   public_configs = [ ":grpc_config" ]
 }