Fixed/added namespace ending comments using clang-tidy. NFC

The patch is generated using this command:

  $ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
      -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
      work/llvm/tools/clang

To reduce churn, not touching namespaces spanning less than 10 lines.

llvm-svn: 240270
diff --git a/clang/unittests/Tooling/TestVisitor.h b/clang/unittests/Tooling/TestVisitor.h
index f4a0039..77a42af 100644
--- a/clang/unittests/Tooling/TestVisitor.h
+++ b/clang/unittests/Tooling/TestVisitor.h
@@ -229,6 +229,6 @@
   std::vector<MatchCandidate> DisallowedMatches;
   std::vector<ExpectedMatch> ExpectedMatches;
 };
-}
+} // namespace clang
 
 #endif