sync: Add DeviceInfo protobuf and supporting code

sync/internal_api/sync_manager_impl_unittest.cc

Index: sync/internal_api/sync_manager_impl_unittest.cc
diff --git a/sync/internal_api/sync_manager_impl_unittest.cc b/sync/internal_api/sync_manager_impl_unittest.cc
index 362e3051ae04838aa7a2443fd78783da56e8ec50..4d8e00c7e0abea096e877103d1d54ceaa6eabf40 100644
--- a/sync/internal_api/sync_manager_impl_unittest.cc
+++ b/sync/internal_api/sync_manager_impl_unittest.cc
@@ -789,6 +789,7 @@ class SyncManagerTest : public testing::Test,
 
   void GetModelSafeRoutingInfo(ModelSafeRoutingInfo* out) {
     (*out)[NIGORI] = GROUP_PASSIVE;
+    (*out)[DEVICE_INFO] = GROUP_PASSIVE;
     (*out)[BOOKMARKS] = GROUP_PASSIVE;
     (*out)[THEMES] = GROUP_PASSIVE;
     (*out)[SESSIONS] = GROUP_PASSIVE;
@@ -1182,7 +1183,7 @@ TEST_F(SyncManagerTest, GetChildNodeIds) {
   const ListValue* nodes = NULL;
   ASSERT_TRUE(return_args.Get().GetList(0, &nodes));
   ASSERT_TRUE(nodes);
-  EXPECT_EQ(6u, nodes->GetSize());
+  EXPECT_EQ(7u, nodes->GetSize());
 }
 
 TEST_F(SyncManagerTest, GetChildNodeIdsFailure) {