Add ServiceAccount Credentials wrapping and handle credentials creation
failure.
	Change on 2015/01/09 by yangg <yangg@google.com>
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=83634736
diff --git a/build.json b/build.json
index 2541572..df59c04 100644
--- a/build.json
+++ b/build.json
@@ -1370,6 +1370,18 @@
       ]
     },
     {
+      "name": "credentials_test",
+      "build": "test",
+      "c++": true,
+      "src": [
+        "test/cpp/client/credentials_test.cc"
+      ],
+      "deps": [
+        "grpc++",
+        "grpc"
+      ]
+    },
+    {
       "name": "alarm_test",
       "build": "test",
       "src": [