Return errors from the Mojo network service using an enum.

mojo/services/network/net_adapters.cc

Index: mojo/services/network/net_adapters.cc
diff --git a/mojo/services/network/net_adapters.cc b/mojo/services/network/net_adapters.cc
index 551481d38810370c9968a546fdf5492b2896ab27..24efee312918d67be86ca26dd64874bea7c3d03b 100644
--- a/mojo/services/network/net_adapters.cc
+++ b/mojo/services/network/net_adapters.cc
@@ -109,7 +109,7 @@ MojoToNetIOBuffer::~MojoToNetIOBuffer() {
 
 NetworkErrorPtr MakeNetworkError(int error_code) {
   NetworkErrorPtr error = NetworkError::New();
-  error->code = error_code;
+  error->code = static_cast<NetworkCode>(error_code);

[jamesr, 2015/02/18 18:43:06]

can you add a set of static_assert<>s that the enum values in mojo match the
ones in net/error/... ? that way if the error codes get out of sync there will
be a compile-time error instead of a mismatched enum value

[ppi, 2015/02/19 14:22:18]

Neat! Done.

   if (error_code <= 0)
     error->description = net::ErrorToString(error_code);
   return error.Pass();