[roll third_party/pigweed] pw_perf_test: Initialize the timer in the unit test

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/152174

https://pigweed.googlesource.com/pigweed/pigweed
third_party/pigweed Rolled-Commits: eafb7fd8c623167..c4a79032934662e
Roller-URL: https://ci.chromium.org/b/8778109205018335889
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ia937d7990b4c72064a98a754c0430e6e7949ecaa
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/152258
Bot-Commit: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
Commit-Queue: Pigweed Integration Roller <pigweed-integration-roller@pigweed.google.com.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index eafb7fd..c4a7903 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit eafb7fd8c623167d40e5357c6028d23005ff319c
+Subproject commit c4a79032934662e3f58504d2777563745af9d65d