Serve skydb on localhost instead of 0.0.0.0.

This patch makes skydb http server available only for local connections.

BUG=460908
R=abarth@chromium.org

Review URL: https://codereview.chromium.org/945663003

tools/debugger/debugger.cc

@@ -51,10 +51,10 @@ class SkyDebugger : public mojo::ApplicationDelegate,
     local_address->family = mojo::NET_ADDRESS_FAMILY_IPV4;
     local_address->ipv4 = mojo::NetAddressIPv4::New();
     local_address->ipv4->addr.resize(4);
-    local_address->ipv4->addr[0] = 0;
+    local_address->ipv4->addr[0] = 127;
     local_address->ipv4->addr[1] = 0;
     local_address->ipv4->addr[2] = 0;
-    local_address->ipv4->addr[3] = 0;
+    local_address->ipv4->addr[3] = 1;
     local_address->ipv4->port = command_port_;
     http_server_factory->CreateHttpServer(GetProxy(&http_server_).Pass(),
                                           local_address.Pass());