Expose ability to download network service impl in SDK.

mojo/public/mojo_application.gni

Index: mojo/public/mojo_application.gni
diff --git a/mojo/public/mojo_application.gni b/mojo/public/mojo_application.gni
index 7661c8885625444b1b6a087f8750409bbcfb84e4..ab82cc6db677ae1acfd5a663841d051411d813a2 100644
--- a/mojo/public/mojo_application.gni
+++ b/mojo/public/mojo_application.gni
@@ -2,6 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/module_args/mojo.gni")
 import("mojo.gni")
 import("mojo_sdk.gni")
 
@@ -84,6 +85,21 @@ template("mojo_native_application") {
         data_deps = [ copy_mojo_shell ]
       }
     }
+
+    if (use_prebuilt_network_service) {
+      copy_network_service =
+          rebase_path("mojo/public/tools:copy_network_service", ".", mojo_root)
+    }
+
+    # Copy the prebuilt network service if using it.

[ppi, 2015/02/10 16:49:50]

nit: tautology, maybe s/using it/needed/?

[blundell, 2015/02/11 21:06:17]

Done.

+    if (use_prebuilt_network_service) {
+      if (defined(data_deps)) {

[ppi, 2015/02/10 16:49:50]

nit: We already have a similar block above, maybe declare data_deps = [] and
then append unconditionally here and above?

[blundell, 2015/02/11 21:06:17]

Done.

+        data_deps += [ copy_network_service ]
+      } else {
+        data_deps = [ copy_network_service ]
+      }
+    }
+
     deps = rebase_path([
                          "mojo/public/c/system",
                          "mojo/public/platform/native:system",