Add wfh to tcmalloc owner.

BUG=None

Review URL: https://codereview.chromium.org/1364193003

Cr-Commit-Position: refs/heads/master@{#350868}
diff --git a/third_party/tcmalloc/OWNERS b/third_party/tcmalloc/OWNERS
index 8b39a54..f1d72974 100644
--- a/third_party/tcmalloc/OWNERS
+++ b/third_party/tcmalloc/OWNERS
@@ -1 +1,2 @@
 jar@chromium.org
+wfh@chromium.org