style(3p/nix): Add braces around single-line conditionals r/771

These were not caught by the previous clang-tidy invocation, but were
instead sorted out using amber[0] as such:

    ambr --regex 'if (\(.+\))\s([a-z].*;)' 'if $1 { $2 }'

[0]: https://github.com/dalance/amber

1 files changed, 3 insertions, 1 deletions

diff --git a/third_party/nix/src/nix-store/graphml.cc b/third_party/nix/src/nix-store/graphml.cc
index a48b19bf9636..07116cda930a 100644
--- a/third_party/nix/src/nix-store/graphml.cc
+++ b/third_party/nix/src/nix-store/graphml.cc
@@ -58,7 +58,9 @@ void printGraphML(ref<Store> store, const PathSet& roots) {
     workList.erase(path);
 
     ret = doneSet.insert(path);
-    if (ret.second == false) continue;
+    if (ret.second == false) {
+      continue;
+    }
 
     ValidPathInfo info = *(store->queryPathInfo(path));
     cout << makeNode(info);