Detect domain-specific resolvers on OS X and disable DnsClient in such cases.

third_party/apple_dnsinfo/README.chromium

Index: third_party/apple_dnsinfo/README.chromium
diff --git a/third_party/apple_dnsinfo/README.chromium b/third_party/apple_dnsinfo/README.chromium
new file mode 100644
index 0000000000000000000000000000000000000000..d3b756bdf33748ae5e0ec55722138ffadc80515b
--- /dev/null
+++ b/third_party/apple_dnsinfo/README.chromium
@@ -0,0 +1,13 @@
+Name: Selected headers for System Configuration Daemon
+Short Name: configd
+URL: http://opensource.apple.com/source/configd/
+Version: 395.7
+License: Apple Public Source License 2.0
+Security Critical: yes
+
+Description:
+Provides dns_config_t which is used by /net/dns/dns_config_service_posix.cc to

[Mark Mentovai, 2013/08/06 15:41:00]

Since all you need is the definition of a struct, you could handle this by just
defining the struct inline in your own code. There is precedent for doing this
in Chrome code, and it’s much easier and ligher-weight than having to bring in a
whole new third_party thing for just one silly header.

However, there’s also precedent for using third_party for this, enough so that
we already have a directory for such code. If you opt to keep this header in
third_party, place it in third_party/apple_apsl, and update the README.chromium
in that directory in the same manner as the entries that are already there.

[szym, 2013/08/06 17:50:25]

Done. Moved to apple_apsl.

+obtain system DNS configuration on Mac OS X.
+
+Local Modifications:
+None.