Make "all user" services work when packaged.

services/service_manager/public/cpp/lib/identity.cc

Index: services/service_manager/public/cpp/lib/identity.cc
diff --git a/services/service_manager/public/cpp/lib/identity.cc b/services/service_manager/public/cpp/lib/identity.cc
index 241b3f48e024a411abc6394878dc843634aa1505..398047fefc4f7d5946b8aac1c23ba994534fe174 100644
--- a/services/service_manager/public/cpp/lib/identity.cc
+++ b/services/service_manager/public/cpp/lib/identity.cc
@@ -18,7 +18,7 @@ Identity::Identity(const std::string& name, const std::string& user_id,
                    const std::string& instance)
     : name_(name),
       user_id_(user_id),
-      instance_(instance.empty() ? GetNamePath(name_) : instance) {
+      instance_(instance) {
   CHECK(!user_id.empty());
   CHECK(base::IsValidGUID(user_id));
 }