Add new text for indicating we are resolving hosts during proxy resolution.

net/proxy/proxy_resolver_mac.cc

Index: net/proxy/proxy_resolver_mac.cc
diff --git a/net/proxy/proxy_resolver_mac.cc b/net/proxy/proxy_resolver_mac.cc
index 935f6fb18c438af4dcfa524f17c8380cd96b0553..ea81418e8c64576c068973212fd5e4cc9a9f6712 100644
--- a/net/proxy/proxy_resolver_mac.cc
+++ b/net/proxy/proxy_resolver_mac.cc
@@ -187,6 +187,11 @@ void ProxyResolverMac::CancelRequest(RequestHandle request) {
   NOTREACHED();
 }
 
+LoadState ProxyResolverMac::GetLoadState(RequestHandle request) const {
+  NOTREACHED();
+  return LOAD_STATE_IDLE;
+}
+
 void ProxyResolverMac::CancelSetPacScript() {
   NOTREACHED();
 }