roll: third_party/pigweed 0d38b28..8db2d07 (3 commits)

8db2d07:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/349253 pw_async2: Add NotifiedDispatcher
295a4fb:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/349273 pw_rpc_transport: Replace constant std::vector with std::array
0537186:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/349252 docs: Remove unused imports

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 0d38b288172b26..8db2d07b7e1e4d
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8697111957640405441
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ibb170a95797ef6e77790b5d1c90e2d7ab8f4951e
Reviewed-on: https://pigweed-review.googlesource.com/c/gonk/+/349333
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index 0d38b28..8db2d07 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 0d38b288172b26d0324abfe4fc525466c2d6dd1b
+Subproject commit 8db2d07b7e1e4dbaf282a6aad41d081b3a68f368