roll: third_party/pigweed 79e14df..39cd52b (3 commits)

39cd52b:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/299413 pw_grpc: Use new ObjectAsBytes()
00739d3:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/299412 pw_span: Remove unnecessary STATIC_ASSERT_EXTENT() macro in cast_test
9c9a414:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/299112 pw_bytes: Introduce pw::ObjectAsBytes() and pw::ObjectAsWritableBytes()

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 79e14df51c6d89..39cd52be62a943
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8711740608230610737
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ie1e4d02d6f9f6a9040b04c23951310448ac17656
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/examples/+/299454
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
diff --git a/third_party/pigweed b/third_party/pigweed
index 79e14df..39cd52b 160000
--- a/third_party/pigweed
+++ b/third_party/pigweed
@@ -1 +1 @@
-Subproject commit 79e14df51c6d8966c4f98f97bd3a5e4f7ceb0a91
+Subproject commit 39cd52be62a943bd2be58d5e85785f95414e753f