Add a test to export two TestService on the same server, only with different
package names. Make sure they work as intended.

This is based on []
	Change on 2015/01/08 by yangg <yangg@google.com>
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=83558743
diff --git a/build.json b/build.json
index d60f4e5..2541572 100644
--- a/build.json
+++ b/build.json
@@ -386,7 +386,9 @@
       "name": "grpc++_test_util",
       "build": "test",
       "src": [
+        "test/cpp/util/messages.proto",
         "test/cpp/util/echo.proto",
+        "test/cpp/util/echo_duplicate.proto",
         "test/cpp/util/create_test_channel.cc",
         "test/cpp/end2end/async_test_server.cc"
       ],
@@ -1348,6 +1350,7 @@
         "test/cpp/end2end/end2end_test.cc"
       ],
       "deps": [
+        "grpc++_test_util",
         "grpc_test_util",
         "grpc++",
         "grpc",